DEF 14A of Castle Biosciences Inc, Apr 8, 2026

DEF 14A of Castle Biosciences Inc

Filed Apr 8, 2026 · FY20250001628280-26-024166

Open on EDGAR

  1. Biographies for Class I Director Nominees (term expiring in 2026)

    Biographies for Class I Director Nominees (term expiring in 2026) Set forth below is biographical information for the Class I director nominees. This includes information regarding each director’s experience, qualifications, attributes or skills that led our Board to recommend them for service as a director.

  2. Biographies for Class I Director Nominees (term expiring in 2026)

    | Name | Experience | Attributes | | Class I - Term Expiring in 2026 | | | | Ellen Goldberg Comp. Committee (Chair) Nominating and Corporate Governance Committee | •Founder and President of CHORD Consulting. •Previously served as Vice President of Marketing at Crescendo Biosciences and led marketing at Genomic Health. •Holds a B.S. degree in chemistry from Yale University and a M.S. in chemistry and an MBA from Stanford University. | •Commercial Execution Experience •Life Science Industry Experience •Digital Health •Regulatory/ Lab Services Reimbursement •Diversity of Skills, Background, and Perspective | | Miles D. Harrison Comp. Committee Nominating and Corporate Governance Committee | •Previously served as the North American President and General Manager at Galderma Laboratories, L.P. Also served as Galderma’s Vice President and General Manager of the Consumer Business Unit. •Holds a B.S. degree in geography from Sheffield Hallam University in the United Kingdom. | •Commercial Execution Experience •Life Science Industry Experience •Financial Analysis & Control Experience | | Tiffany P. Olson Audit Committee Nominating and Corporate Governance Committee (Chair) | •Previously served as President of Nuclear & Precision Health Solutions at Cardinal Health. •Previously served as President at NaviMed and CEO and President of Roche Diagnostics Corporation. •Holds a B.S. degree in business from University of Minnesota and MBA from the University of St. Thomas. | •Commercial Execution Experience •Life Science Industry Experience •Financial Analysis & Control Experience •Digital Health •Health System Experience •Diversity of Skills, Background, and Perspective |

  3. Biographies for Class I Director Nominees (term expiring in 2026)

    | Castle Biosciences 2026 Proxy Statement | 3 |

  4. Biographies for Class I Director Nominees (term expiring in 2026)

    | Proxy Summary | Table of Contents |

  5. Biographies for Class II and Class III Directors

    Biographies for Class II and Class III Directors Set forth below is biographical information for the Class II and Class III directors, whose terms of office as a director will continue after the Annual Meeting. This includes information regarding each director’s experience, qualifications, attributes or skills that led our Board to recommend them for service as a director.

  6. Biographies for Class II and Class III Directors

    | Name | Experience | Attributes | | Class II - Term Expiring in 2027 | | | | Daniel M. Bradbury Board Chair | •Currently serves on the board of directors of Equillium, Inc. and Vivani Medical Inc. •Previously served as an executive and CEO of Equillium Inc. •Managing member of BioBrit, LLC. •Previously served as President, CEO and Director of Amylin Pharmaceuticals, Inc. •Serves on the board of directors of numerous privately held companies. •Holds a B.S. degree in pharmacy from Nottingham University and a Diploma in Management Studies from University of West London of Higher Education in the United Kingdom. | •Commercial Execution •Life Science Industry Experience •Financial Analysis & Control Experience •R&D Scientific Leadership •Regulatory/Lab Services Reimbursement | | Rodney Cotton Audit Committee Comp. Committee | •Previously served as Senior Vice President, Chief of Staff and Head of Strategy and Transformation at Roche Diagnostics. Also served as Interim Head of Communications and Senior Vice President, Commercial Operations/West Zone. •Serves on the board of directors of numerous privately held companies. •Holds a B.A. in Biological Sciences & Technology from the University of California, Santa Barbara, an M.S. in Strategic Management from the University of Southern California, and an MBA from the California State University Dominguez Hills. | •Commercial Execution •Life Science Industry Experience •Financial Analysis & Control Experience •Digital Health •Health System Experience •Regulatory/Lab Services Reimbursement •Diversity of Skills, Background, and Perspective |

  7. Biographies for Class II and Class III Directors

    | 4 | Castle Biosciences 2026 Proxy Statement |

  8. Biographies for Class II and Class III Directors

    | Table of Contents | Proxy Summary |

  9. Biographies for Class II and Class III Directors

    | Name | Experience | Attributes | | Class III - Term Expiring in 2028 | | | | Kimberlee S. Caple Audit Committee Nominating and Corporate Governance Committee | •In March 2025, she retired from her position as the President of the Genetic Science Division, at Thermo Fisher Scientific Inc. •Previously served as the Vice President and General Manager of Genetics Sciences of the Genetics Sciences Business and the Vice President and General manager for the Capillary Electrophoresis Business Unit at Thermo Fisher Scientific Inc. •Holds a B.S. degree in biology from Purdue University. | •Life Science Industry Experience •Financial Analysis & Control Experience •Health System Experience •R&D Scientific Leadership •Regulatory/Lab Services Reimbursement •Diversity of Skills, Background, and Perspective | | G. Bradley Cole Audit Committee (Chair) Comp. Committee | •Previously served as General Manager of Precision Oncology, a unit of Exact Sciences Corporation. •Previously served as Chief Financial Officer and Chief Operating Officer at Genomic Health. •Previously held Chief Financial Officer positions at multiple publicly traded companies, including Applied Biosystems, Inc. •Holds a B.S. degree in accounting from Biola University and an MBA from San Jose State University. | •Commercial Execution Experience •Life Science Industry Experience •Financial Analysis & Control Experience •Digital Health •Regulatory/Lab Services Reimbursement •Cybersecurity | | Derek J. Maetzold President and CEO | •Founded Castle Biosciences and has served as our President, CEO and a member of our Board since inception. •Previously held leadership roles at Encysive Pharmaceuticals, Schering-Plough Corporation (now Merck), Integrated Communications, Amylin Pharmaceuticals and Sandoz Pharmaceuticals (now a division of Novartis). •Currently serves as a director of PreludeDx, Coalition for 21st Century Medicine and IMPACT Melanoma. •Holds a B.S. degree in Biology from George Mason University. | •Commercial Execution Experience •Life Science Industry Experience •Financial Analysis & Control Experience •Digital Health •Health System Experience •R&D Scientific Leadership •Regulatory/Lab Services Reimbursement •Diversity of Skills, Background, and Perspective •Cybersecurity |

  10. Biographies for Class II and Class III Directors

    | Castle Biosciences 2026 Proxy Statement | 5 |

  11. Biographies for Class II and Class III Directors

    | Proxy Summary | Table of Contents |

  12. Class I Director Nominees for Election for a Three-Year Term Expiring at Castle’s 2029 Annual Meeting of Stockholders

    Class I Director Nominees for Election for a Three-Year Term Expiring at Castle’s 2029 Annual Meeting of Stockholders

  13. Class I Director Nominees for Election for a Three-Year Term Expiring at Castle’s 2029 Annual Meeting of Stockholders

    | | | Ellen Goldberg She has served as a member of our board of directors since July 2021. Ms. Goldberg has served as the Founder and President of CHORD Consulting since 2011, where she works with executives of innovative diagnostics companies to develop and commercialize novel products. She has focused her career on ground-breaking technologies in life-threatening and life-altering diseases. Ms. Goldberg served as Vice President of Marketing at Crescendo Bioscience, developer of Vectra DA®, a multi-biomarker blood test that predicts joint damage and enables treatment changes to improve outcomes in rheumatoid arthritis. Prior to Crescendo, Ms. Goldberg led marketing at Genomic Health, where she launched the Oncotype DX® Breast Cancer Assay, which went from inception to >$108MM in annual revenue during her tenure, and directed the commercial side of product development for tests in colon cancer, prostate cancer and ductal carcinoma in situ. Ms. Goldberg began her career as a strategy consultant with Booz Allen & Hamilton and developed new products at ALZA Corporation. She has an M.S in Chemistry and an MBA from Stanford University and a B.S. in Chemistry from Yale University. Ms. Goldberg is also a fellow of the Aspen Institute’s Health Innovators Fellowship Program. | | | Independent Director | | | | Age: 52 | | | | Director since: 2021 | | | | Committees: •Compensation Committee (Chair) •Nominating and Corporate Governance Committee | | | | | Our Nominating and Corporate Governance Committee and board of directors believe Ms. Goldberg’s expertise in the development and commercialization of diagnostic tests and commercial leadership experience in the diagnostics qualify her to serve on our board of directors. |

  14. Class I Director Nominees for Election for a Three-Year Term Expiring at Castle’s 2029 Annual Meeting of Stockholders

    | Castle Biosciences 2026 Proxy Statement | 9 |

  15. Class I Director Nominees for Election for a Three-Year Term Expiring at Castle’s 2029 Annual Meeting of Stockholders

    | Proposal One | Table of Contents |

  16. Class I Director Nominees for Election for a Three-Year Term Expiring at Castle’s 2029 Annual Meeting of Stockholders

    | | | Miles D. Harrison Miles has served as a member of our board of directors since April 2020 and as Chair of the Compensation Committee from 2020 through 2025. In October 2025, Miles accepted the role of CEO and President of Conexeu Sciences Inc. a pre-clinical company focused on building a new class of regenerative tissue therapies. From April 2021 through July 2025 Miles co-founded a medical aesthetics company ‘Novaestiq’ which was acquired by Waldencast (WALD) 4 years later. Earlier, from 2016 through 2021, Miles spent 5 years as the North American President and General Manager of Galderma Laboratories, L.P., a global dermatology company. During his tenure at Galderma, he managed multiple launches across the company’s pure-play dermatology portfolio (Rx, Consumer and Aesthetics) and helped shape strategy as a member of the Global Leadership Team. Prior to being President, Mr. Harrison served as Galderma’s U.S. VP and General Manager of the Consumer Business from 2014, launching several brands and completing the first Rx to OTC switch in acne in the U.S. for more than 30 years. Mr. Harrison spent most of his career at Novartis International AG, a global healthcare company based in Basle, Switzerland. From 1987 to 2014, Mr. Harrison held multiple leadership positions of increasing responsibility at Novartis across Consumer Health, Oncology, Nutrition and Pharmaceuticals in operational and functional leadership roles. Mr. Harrison holds an Honors Degree in Geography from Sheffield Hallam University in the United Kingdom, and has lived and worked in the U.K., Europe, Middle East, Latin America, and the past 20+ years in the U.S. | | | Independent Director | | | | Age: 61 | | | | Director since: 2020 | | | | Committees: •Compensation Committee •Nominating and Corporate Governance Committee | | | | | Our Nominating and Corporate Governance Committee and board of directors believe Mr. Harrison’s experience in dermatology combined with his strategic leadership skills, as an executive in the pharmaceutical and consumer healthcare industry, qualify him to serve on our board of directors. |

  17. Class I Director Nominees for Election for a Three-Year Term Expiring at Castle’s 2029 Annual Meeting of Stockholders

    | 10 | Castle Biosciences 2026 Proxy Statement |

  18. Class I Director Nominees for Election for a Three-Year Term Expiring at Castle’s 2029 Annual Meeting of Stockholders

    | Table of Contents | Proposal One |

  19. Class I Director Nominees for Election for a Three-Year Term Expiring at Castle’s 2029 Annual Meeting of Stockholders

    | | | Tiffany P. Olson She has served as a member of our board of directors since May 2021. From July 2013 to October 2021, Ms. Olson served as President of Nuclear & Precision Health Solutions at Cardinal Health, Inc., a multinational health care services company. From 2011 to 2013, Ms. Olson served as President of NaviMed, a consulting firm focused exclusively on the healthcare industry. From 2009 to 2011, Ms. Olson led Diagnostics at Eli Lilly and Company. From 2005 to 2008, Ms. Olson served as the CEO and President of Roche Diagnostics Corporation, where from 1997 to 2005 she held various roles of increasing responsibility. Ms. Olson currently serves on the boards of Langham Logistics, a privately held freight management company, MIMEDX, a publicly traded company, The Education and Research Foundation for Nuclear Medicine and Molecular Imaging, The American Cancer Society in Indiana, and is a Partner at Trusted Health Advisors. Ms. Olson holds an MBA from the University of St. Thomas, St. Paul, Minnesota, and a Bachelor of Science, Business degree from the University of Minnesota. | | | Independent Director | | | | Age: 66 | | | | Director since: 2021 | | | | Committees: •Audit Committee •Nominating and Corporate Governance Committee (Chair) | | | | | Our Nominating and Corporate Governance Committee and board of directors believe that Ms. Olson’s extensive experience in life science and her strategic leadership skills as an executive in the pharmaceutical, diagnostics and health services industry qualify her to serve on our board of directors. |

  20. Class I Director Nominees for Election for a Three-Year Term Expiring at Castle’s 2029 Annual Meeting of Stockholders

    | FOR | The Board of Directors Recommends a Vote “FOR ALL” Class I Director Nominees. |

  21. Class I Director Nominees for Election for a Three-Year Term Expiring at Castle’s 2029 Annual Meeting of Stockholders

    | Castle Biosciences 2026 Proxy Statement | 11 |

  22. Class I Director Nominees for Election for a Three-Year Term Expiring at Castle’s 2029 Annual Meeting of Stockholders

    | Proposal One | Table of Contents |

  23. Class II Directors Continuing in Office Until Castle’s 2027 Annual Meeting of Stockholders

    Class II Directors Continuing in Office Until Castle’s 2027 Annual Meeting of Stockholders

  24. Class II Directors Continuing in Office Until Castle’s 2027 Annual Meeting of Stockholders

    | | | Daniel M. Bradbury He has served as a member of our board of directors since September 2012, and as chair of our board of directors since September 2014. Since October 2025, Mr. Bradbury has served as Chairman of Equillium, Inc., a publicly traded biotechnology company, that he cofounded and also served as its Executive Chairman from January 2020 until September 2025, CEO from June 2018 until December 2019 and President from March 2017 until June 2018. Mr. Bradbury is the founder of, and has served as the managing member of BioBrit, LLC, a life sciences consulting and investment firm, since September 2012. Mr. Bradbury served as President, CEO and a director of Amylin Pharmaceuticals, Inc. from March 2007 until Amylin’s acquisition by Bristol-Myers Squibb Company in August 2012. Prior to Amylin, Mr. Bradbury worked in marketing and sales for ten years at SmithKline Beecham Pharmaceuticals. Mr. Bradbury serves on the board of Equillium, Inc. and Vivani Medical Inc., as well as a number of privately held companies. He previously served on the board of directors of the following publicly traded companies: Intercept Pharmaceuticals, Inc., a biopharmaceutical company, from 2016 to 2023; Biocon Limited, an Indian biopharmaceutical company, from 2013 to 2022; Corcept Therapeutics, Inc., a pharmaceutical company, from 2012 to 2019; Geron Corporation, a biotechnology company, from 2012 to 2019; and Illumina, Inc., a biotechnology company, from 2004 to 2017. Mr. Bradbury holds a Bachelor of Pharmacy from Nottingham University and a Diploma in Management Studies from the University of West London in the United Kingdom. | | | Independent Board Chair | | | | Age: 64 | | | | Director since: 2012 | | | | Committees: •None | | | | | Our Nominating and Corporate Governance Committee and board of directors believe that Mr. Bradbury’s extensive experience as a life sciences executive and his other executive and boards of directors experience qualify him to serve on our board of directors. |

  25. Class II Directors Continuing in Office Until Castle’s 2027 Annual Meeting of Stockholders

    | 12 | Castle Biosciences 2026 Proxy Statement |

  26. Class II Directors Continuing in Office Until Castle’s 2027 Annual Meeting of Stockholders

    | Table of Contents | Proposal One |

  27. Class II Directors Continuing in Office Until Castle’s 2027 Annual Meeting of Stockholders

    | | | Rodney Cotton He has served as a member of our board of directors since March 2024. From 2001 to 2023, Mr. Cotton served various roles at Roche Diagnostics, a diagnostics healthcare company. These roles included, most recently, Senior Vice President, Chief of Staff and Head of Strategy and Transformation from January 2020 to June 2023, Interim Head of Communications from May 2022 to October 2022 and Senior Vice President, Commercial Operations from April 2017 to January 2020. Mr. Cotton currently serves as CEO of Cotton Ventures, LLC and also on the board of directors of various privately held pharmaceutical, life sciences, venture capital and technology companies. Mr. Cotton completed a Mergers & Acquisition Executive Program at Harvard Business School as well as a Director’s Consortium Executive Program at Stanford Graduate School of Business. Mr. Cotton holds an MBA from the California State University Dominguez Hills, an M.S. in Strategic Management from the University of Southern California, and a B.A. in Biological Sciences & Technology from the University of California, Santa Barbara. | | | Independent Director | | | | Age: 66 | | | | Director since: 2024 | | | | Committees: •Audit Committee •Compensation Committee | | | | | Our Nominating and Corporate Governance Committee and board of directors believe that Mr. Cotton’s extensive experience and strategic leadership skills as a life science and clinical diagnostic executive qualify him to serve on our board of directors. |

  28. Class II Directors Continuing in Office Until Castle’s 2027 Annual Meeting of Stockholders

    | Castle Biosciences 2026 Proxy Statement | 13 |

  29. Class II Directors Continuing in Office Until Castle’s 2027 Annual Meeting of Stockholders

    | Proposal One | Table of Contents |

  30. Class III Directors Continuing in Office Until Castle’s 2028 Annual Meeting of Stockholders

    Class III Directors Continuing in Office Until Castle’s 2028 Annual Meeting of Stockholders

  31. Class III Directors Continuing in Office Until Castle’s 2028 Annual Meeting of Stockholders

    | | | Kimberlee S. Caple She has served as a member of our board of directors since July 2021. In March 2025, she retired from her position as President, Genetic Science Division (“GSD”) at Thermo Fisher Scientific Inc. From mid-2020 through January 2022, Ms. Caple was the Vice President and General Manager of the Genetics Sciences Business (“GSB”), a part of the Genetic Sciences Division within Thermo Fisher Scientific. From 2017 through mid-2020, Ms. Caple was the Vice President and General Manager for the Capillary Electrophoresis Business Unit, a part of the GSD. The GSD is made up of five business units which develop, manufacture and commercialize genetic analysis tools and solutions that serve the healthcare, forensic, research and pharmaceutical/biotechnology markets globally. Ms. Caple has a B.S. degree in Biology from Purdue University. | | | Independent Director | | | | Age: 64 | | | | Director since: 2021 | Our Nominating and Corporate Governance Committee and board of directors believe that Ms. Caple’s extensive experience and strategic leadership skills as a life science and clinical diagnostic executive qualify her to serve on our board of directors. | | | Committees: •Audit Committee •Nominating and Corporate Governance Committee | |

  32. Class III Directors Continuing in Office Until Castle’s 2028 Annual Meeting of Stockholders

    | 14 | Castle Biosciences 2026 Proxy Statement |

  33. Class III Directors Continuing in Office Until Castle’s 2028 Annual Meeting of Stockholders

    | Table of Contents | Proposal One |

  34. Class III Directors Continuing in Office Until Castle’s 2028 Annual Meeting of Stockholders

    | | | G. Bradley Cole He has served as a member of our board of directors since December 2018 and Chairman of the Castle Audit Committee since May 2019. From November 2019 until April 2020, Mr. Cole served as General Manager, Precision Oncology, a unit of Exact Sciences Corporation, a molecular diagnostics company, following Exact Science Corporation’s acquisition of Genomic Health, Inc. From June 2004 to November 2019, Mr. Cole served as Chief Financial Officer of Genomic Health, Inc., a publicly traded global provider of genomic-based diagnostic tests, where he also served as Chief Operating Officer from January 2009 until March 2018. Mr. Cole previously held Chief Financial Officer positions at multiple publicly traded companies, including Applied Biosystems, Inc. Since July of 2020, Mr. Cole has served on the board of Kiniksa Pharmaceuticals (KNSA), a public pharmaceutical company, and is a member of the audit committee. Mr. Cole also is the Vice Chairman of the Board of Trustees of Biola University where he has served since 2002. Mr. Cole holds a B.S. degree in Business - Accounting from Biola University and an MBA from San Jose State University. | | | Independent Director | | | | Age: 70 | | | | Director since: 2018 | | | | Committees: •Audit Committee (Chair) •Compensation Committee | | | | | Our Nominating and Corporate Governance Committee and board of directors believe that Mr. Cole’s extensive experience in finance and operations as a public company executive and knowledge of the diagnostics industry qualify him to serve on our board of directors. |

  35. Class III Directors Continuing in Office Until Castle’s 2028 Annual Meeting of Stockholders

    | | | Derek J. Maetzold He founded Castle Biosciences in September 2007 and has served as our President and Chief Executive Officer and as a member of our board of directors since inception. Previously, Mr. Maetzold held leadership roles at Encysive Pharmaceuticals, Schering-Plough Corporation (now Merck), Integrated Communications, Amylin Pharmaceuticals and Sandoz Pharmaceuticals (now a division of Novartis). Mr. Maetzold currently serves as a director of PreludeDx, Coalition for 21st Century Medicine and IMPACT Melanoma. He has contributed to the discovery, development and commercialization of multiple diagnostic tests in cancers, has co-authored multiple scientific publications and is a co-inventor of a number of technologies at Castle Biosciences and Encysive Pharmaceuticals. Mr. Maetzold holds a B.S. degree in Biology from George Mason University and completed additional coursework at the University of Calgary Health Sciences Center and the MBA program at the University of California, Riverside. | | | Director | | | | Age: 64 | | | | Director since: 2007 | | | | Committees: •None | | | | | Our Nominating and Corporate Governance Committee and board of directors believe that Mr. Maetzold’s experience as our founder, director and as our President and CEO, as well as his expertise in the development and commercialization of diagnostic tests, qualify him to serve on our board of directors. |

  36. Class III Directors Continuing in Office Until Castle’s 2028 Annual Meeting of Stockholders

    | Castle Biosciences 2026 Proxy Statement | 15 |

  37. Class III Directors Continuing in Office Until Castle’s 2028 Annual Meeting of Stockholders

    | Information Regarding the Board of Directors and Corporate Governance |

  38. •Tiffany P. Olson

    | Delegation Authority The Compensation Committee may delegate to one or more officers of the Company the authority to grant, amend and/or administer awards of cash or options or other equity securities to any employees or other service providers of the Company who, in either case, are not Section 16 officers under the Company’s incentive-compensation or other equity-based plans as the Compensation Committee deems appropriate. For more information, see the “Compensation Committee Processes and Procedures” section of this Proxy Statement. | •Reviewing and assessing the independence of compensation consultants, legal counsel and other advisors as required by Section 10C of the Exchange Act; •Reviewing the Company’s peer group to determine pay levels; •Administering our equity incentive plans; •Establishing policies with respect to equity compensation arrangements; •Reviewing the competitiveness of our executive compensation programs and evaluating the effectiveness of our compensation policy and strategy in achieving expected benefits to us; •Reviewing and making recommendations to the full board of directors regarding the terms of any employment agreements, severance arrangements, change in control protections and any other compensatory arrangements for our executive officers; •Reviewing with management and approving our disclosures under the caption “Compensation Discussion and Analysis” in our periodic reports or proxy statements to be filed with the SEC, to the extent such caption is required to be included in any such report or proxy statement; •Preparing the report that the SEC requires in our annual proxy statement; •Reviewing and assessing on an annual basis the performance of the Compensation Committee and the Compensation Committee Charter; and •Overseeing policies and strategies relating to human capital management. | | Role of Executive Officers and Compensation Consultant See the “Compensation Committee Processes and Procedures” section below and “Role of Independent Compensation Consultant” in the “Compensation Discussion and Analysis” section of this Proxy Statement for a discussion of the role of our executive officers and compensation consultant in determining executive compensation. | | | Compensation Committee Report The report of the Compensation Committee is set forth under “Compensation Committee Report” in the “Compensation Discussion and Analysis” section of this Proxy Statement. | |

  39. •Tiffany P. Olson

    only after taking into consideration six factors, prescribed by the SEC and Nasdaq Listing Rule 5605(d)(3)(D), that bear upon the adviser’s independence; however, there is no requirement that any adviser be independent. During the fiscal year ended December 31, 2025, after taking into account the considerations prescribed by the SEC and Nasdaq described above, the Company engaged AON’s Human Capital Solutions Practice, a division of AON plc (“AON”), as its compensation consultant. AON was retained to provide an assessment of the Company’s executive compensation programs in comparison to executive compensation programs at selected publicly traded peer companies. As part of its engagement, AON was requested by the Compensation Committee to develop the peer group of comparative companies and to perform analyses of compensation levels for that group. AON developed peer group and related recommendations that were presented to the Compensation Committee for its consideration. Under its charter, the Compensation Committee may form, and delegate authority to, subcommittees as appropriate. The Compensation Committee has delegated authority to the CEO and Chief Financial Officer, acting jointly (together, the “Authorized Officers”), to grant, without any further action required by the Compensation Committee, equity awards to employees who are below the level of vice president of the Company, within specific approved ranges, which vary by position classification, as set forth by the Compensation Committee. The purpose of this delegation of authority is to enhance the flexibility of equity award administration within the Company and to facilitate the timely grant of equity awards to non-executive employees and consultants under the 2019 Equity Incentive Plan (the “2019 Plan”) within specified limits approved by the Compensation Committee. Typically, as part of its oversight function, the Compensation Committee will review the list of predetermined schedule grants made by the Authorized Officers, without the use of material nonpublic information, at each regularly scheduled in-person meeting. Predetermined grants are issued bi-monthly, mid-month and at the end of the month, with a standard four-year vesting term. See also “Pay Versus Performance—Policies and Practices Related to the Grant of Certain Equity Awards Close in Time to the Release of Material Nonpublic Information.” The Compensation Committee holds one or more meetings at the end of the year and/or during the first quarter of the year to discuss and make recommendations to the board of directors for annual compensation adjustments, annual bonuses, annual equity awards, and new corporate performance objectives. For executives other than the CEO, the Compensation Committee solicits and considers evaluations and recommendations submitted to the Compensation Committee by the CEO. In the case of the CEO, the evaluation of his performance is conducted by the Compensation Committee and is recommended to the board of directors.

  40. DIRECTOR COMPENSATION

    DIRECTOR COMPENSATION The following table sets forth in summary certain information concerning the compensation that was earned by each of our non-employee directors during the fiscal year ended December 31, 2025:

  41. DIRECTOR COMPENSATION

    | Name | Fees Earned or Paid in Cash ($) | Stock Awards ($)(1)(2) | Option Awards ($)(1)(3) | Total ($) | | Daniel M. Bradbury | 97,056 | 217,169 | — | 314,225 | | Kimberlee S. Caple | 64,019 | 217,169 | — | 281,188 | | G. Bradley Cole | 76,519 | 217,169 | — | 293,688 | | Rodney Cotton(4) | 66,519 | 250,763 | — | 317,282 | | Ellen Goldberg | 69,113 | 217,169 | — | 286,282 | | Miles D. Harrison | 66,425 | 217,169 | — | 283,594 | | Tiffany P. Olson | 69,019 | 217,169 | — | 286,188 |

  42. DIRECTOR COMPENSATION

    (1)In accordance with SEC rules, this column reflects the aggregate grant date fair value of the stock option and all restricted stock units (“RSU”) awards granted in 2025 computed in accordance with Financial Accounting Standards Board (“FASB”) Accounting Standards Codification Topic (“ASC 718”). Accordingly, these amounts will vary from the stated value of the awards in the Non-Employee Director Compensation Policy described below. Assumptions used in the calculation of these amounts are described in Note 14 to our consolidated financial statements appearing in our Annual Report on Form 10-K for the fiscal year ended December 31, 2025. The amounts reported in this column reflect the accounting value of these awards and do not correspond to the actual economic value that ultimately may be realized by our non-employee directors. (2)As of December 31, 2025, the number of shares outstanding under all RSUs held by Mr. Cotton and each of our other non-employee directors was 24,326 and 13,667, respectively. (3)As of December 31, 2025, the aggregate number of shares subject to all outstanding options to purchase our common stock held by our non-employee directors were: Mr. Bradbury, 49,921, Ms. Caple, 13,012, Mr. Cole, 74,669, Ms. Goldberg, 13,012, Mr. Harrison, 35,026, and Ms. Olson, 16,962. (4)Mr. Cotton received an equity award on May 8, 2025 to address a grant of RSUs made to him in 2024 that was smaller at the time of grant due to the annual director compensation limit. This grant consisted of 1,952 RSUs vested in full on May 21, 2025.

  43. DIRECTOR COMPENSATION

    | Castle Biosciences 2026 Proxy Statement | 29 |

  44. DIRECTOR COMPENSATION

    | Information Regarding the Board of Directors and Corporate Governance | Table of Contents |

  45. DIRECTOR COMPENSATION

    Mr. Maetzold, our President and CEO, is also a member of our board of directors but did not receive any additional compensation for his service as a director. See the section titled “Compensation Discussion and Analysis—Elements of Our Executive Compensation Program” below for more information regarding the compensation earned by Mr. Maetzold. We have reimbursed and will continue to reimburse all of our non-employee directors for their travel, lodging and other reasonable expenses incurred in attending meetings of our board of directors and committees of our board of directors.

  46. Non-Employee Director Compensation Policy

    Non-Employee Director Compensation Policy Our board of directors has adopted a non-employee director compensation policy that is applicable to each member of our board of directors who is not also serving as an employee or consultant. Our Compensation Committee reviews non-employee director compensation levels at least annually and either approves, or submits recommendations to our Board with respect to, any changes in non-employee director compensation levels. Cash Compensation The following table sets forth the annual cash retainer from January 1, 2025 through the time immediately preceding the closing of the polls of the 2025 Annual Meeting of Stockholders on May 22, 2025:

  47. Non-Employee Director Compensation Policy

    | Name | Members ($) | Chair ($) | | Directors | 47,500 | 45,000(1) | | Audit Committee | 10,000 | 20,000(2) | | Compensation Committee | 7,500 | 20,000(2) | | Nominating and Corporate Governance Committee | 5,000 | 10,000(2) |

  48. Non-Employee Director Compensation Policy

    (1)An additional cash retainer for service as chair of the board of directors. (2)An additional cash retainer for service as Chair of the Audit Committee, Compensation Committee and the Nominating and Corporate Governance Committee, respectively (committee chairs will not receive the cash retainer as a member of the respective committee in addition to the committee chair service retainer). In 2025, AON, our Compensation Committee’s independent compensation consultant reviewed the market competitiveness of our non-employee director compensation policy relative to our compensation peer group and recommended certain changes based on governance best practices and market trends to ensure we can attract and retain a highly qualified board of directors. Our Compensation Committee approved an amendment to our non-employee director compensation policy effective on May 22, 2025 that provided for an increase to the annual cash retainer for service (a) on the board of directors from $47,500 to $50,000 and (b) as chair of the board of directors from $45,000 to $50,000. Such amendment also provided for an increase to the target grant date fair value of annual equity awards awarded to continuing directors from $200,000 to $250,000. The change to the annual cash retainers became effective immediately following the 2025 Annual Meeting of Stockholders and the change to the target grant date fair value of equity awards applied to awards granted at the 2025 Annual Meeting of Stockholders. Our Compensation Committee also approved an amendment to our non-employee director compensation policy effective on August 5, 2025 that provided for (i) a six-month service period by any new director that must be satisfied before such new director becomes eligible to receive an annual grant of equity award and (ii) proration of a director’s first annual equity award based on the number of completed months served, subject to the new six-month service period required by any new director for eligibility to receive an annual grant of equity awards.

  49. Non-Employee Director Compensation Policy

    | 30 | Castle Biosciences 2026 Proxy Statement |

  50. Non-Employee Director Compensation Policy

    | Table of Contents | Information Regarding the Board of Directors and Corporate Governance |

  51. Non-Employee Director Compensation Policy

    •New Directors: Upon joining the Board, directors receive an initial equity grant valued at $350,000, consisting of a RSU award covering a number of shares of common stock generally calculated by dividing $350,000 by the average of the closing prices of our common stock for each trading day within the 30 calendar days prior to the grant date rounded down to the nearest whole share. The shares subject to the initial equity grant will vest in a series of three successive equal annual installments over the three-year period measured from the date of grant. •Current Directors: As mentioned above, effective for the annual equity awards granted at the 2025 Annual Meeting of Stockholders, annually, following each annual meeting of stockholders, our directors receive an equity grant valued at $250,000, consisting of an RSU award covering a number of shares of common stock calculated by dividing $250,000 by the average of the closing prices of our common stock for each trading day within the 30 calendar days prior to the grant date rounded down to the nearest whole share. The shares subject to the annual equity grant vest in full on the earlier of a) the one-year anniversary of the date of grant or b) the day immediately preceding the next annual meeting following the date of grant. Also, as mentioned above, the six-month service requirement and proration mechanics apply to annual equity awards made on or after August 5, 2025. In making the decision to allocate grants as RSUs, the Compensation Committee has continued to monitor the market trends and the investor preference for the Board to be aligned long-term with stockholder value creation. The Board believes that RSUs provide compensation for current service and reinforce the ownership culture that we have built. Each of the RSU grants described above were, or will be, granted under and subject to the terms of the 2019 Plan. Each such RSU grant will vest subject to the director’s continuous service to us, provided that each RSU will vest in full upon a change in control (as defined in the 2019 Plan). An eligible director may decline all or any portion of his or her compensation by giving notice to us prior to the date cash may be paid or equity awards are to be granted, as the case may be. Pursuant to our 2019 Plan, in any calendar year, the total cash fees paid, together with equity awards granted, to any non-employee director for service on the Board will not exceed $350,000 in total value or, with respect to the calendar year in which a non-employee director is first appointed or elected to the Board, $550,000 and, in each case, calculating the value of equity awards based on the grant date value of such awards for financial reporting purposes.

  52. Executive Compensation

    | Proposal 4: Approval of the Company’s Non-Employee Director Compensation Policy |

  53. Summary of Director Compensation Policy

    Summary of Director Compensation Policy The following summary of the material terms of the Director Compensation Policy is qualified in its entirety by reference to the full text of the Director Compensation Policy, a copy of which is attached as Appendix A to this Proxy Statement and which is incorporated by reference into this Proposal 4. Stockholders should refer to Appendix A for a more complete description of the Director Compensation Policy.

  54. Cash Compensation

    The Director Compensation Policy provides for equity grants, beginning with annual grants to be made following the Annual Meeting. Initial Grant for New Directors: Upon joining the Board, non-employee directors will automatically receive an initial equity grant (the “Initial Grant”) valued at $400,000, consisting of a RSU award covering a number of shares of common stock calculated by dividing $400,000 by the average of the closing prices of our common stock for each trading day within the 30 calendar days prior to the grant date (such price, the “Average Price”), rounded down to the nearest whole share (the “Total Initial Shares”). In the event that more than one non-employee director is elected or appointed within a single calendar year, for each non-employee director elected or appointed after the first election or appointment of a non-employee director in such calendar year (each, a “Subsequent Director”), if the Average Price calculated for purposes of determining the Total Initial Shares underlying the Initial Grant for a Subsequent Director has not increased or decreased by more than 10% compared to the Average Price calculated for purposes of determining the Total Initial Shares underlying the Initial Grant for the first non-employee director elected or appointed in that same calendar year (the “First Director”), then the Total Initial Shares underlying the Initial Grant for such Subsequent Director shall be equal to the Total Initial Shares calculated for the First Director. The shares subject to the Initial Grant will vest in a series of three successive equal annual installments over the three-year period measured from the grant date. Annual Grant: At the close of business on the date of each annual meeting of stockholders, beginning with the Annual Meeting, each of our non-employee directors will automatically receive an annual equity grant (the “Annual Grant”) valued at $260,000, consisting of an RSU award covering a number of shares of common stock calculated by dividing $260,000 by the Average Price, rounded down to the nearest whole share. The shares subject to the Annual Grant vest in full on the earlier of a) the one-year anniversary of the date of grant or b) the day immediately preceding the next annual meeting following the date of grant. In addition, the Director Compensation Policy provides for (i) a six-month service period by any new non-employee director that must be satisfied before such new non-employee director becomes eligible to receive an Annual Grant and (ii) proration of a non-employee director’s first Annual Grant based on the number of completed months served, subject to the six-month service period required by any new non-employee director for eligibility to receive an Annual Grant. Each Initial Grant and Annual Grant will vest subject to the non-employee director’s continuous service to us, provided that each such grant will vest in full upon a change in control (as defined in the 2019 Plan).

  55. Additional Requirements

    Additional Requirements In making any future changes to compensation payable to non-employee directors, the Board or Compensation Committee will evaluate the practices of the peer group of companies that serve as references for executive compensation benchmarking, as well as then-current general best practices regarding director compensation. The Compensation Committee will review the Director Compensation Policy on at least an annual basis and engage an independent compensation consultant to assist in such review. Furthermore, the Company will not permit compensation to be paid to non-employee directors for their service as such other than as provided for in the Director Compensation Policy (as amended from time to time), unless there are extraordinary circumstances as determined by the Compensation Committee or the Board. All payments to non-employee directors will be disclosed in accordance with applicable law, regulations and exchange or national market system requirements.

  56. Additional Requirements

    | FOR | The Board of Directors Recommends a Vote “FOR” Approval of the Company’s Non-Employee Director Compensation Policy. |

  57. Additional Requirements

    The following table sets forth certain information regarding the ownership of the Company’s common stock as of March 20, 2026 by (i) each of our directors; (ii) each of our NEOs; (iii) all of our current executive officers and directors as a group; and (iv) all those known by the Company to be beneficial owners of more than 5% of its common stock. Applicable percentages are based on 30,290,086 shares outstanding on March 20, 2026, adjusted as required by rules promulgated by the SEC. Except as otherwise noted below, the address for each person or entity listed in the table is c/o Castle Biosciences, Inc., 1500 W. Parkwood Ave, Suite 400, Friendswood, Texas 77546. We have determined beneficial ownership in accordance with the rules of the SEC. These rules generally attribute beneficial ownership of securities to persons who possess sole or shared voting power or investment power with respect to those securities. In addition, the rules include shares of common stock issuable pursuant to the exercise of stock options or RSUs that are either immediately exercisable or settleable or exercisable or settleable on or before May 19, 2026, which is 60 days after March 20, 2026. These shares are deemed to be outstanding and beneficially owned by the person holding those options or RSUs for the purpose of computing the percentage ownership of that person, but they are not treated as outstanding for the purpose of computing the percentage ownership of any other person. Unless otherwise indicated, the persons or entities identified in this table have sole voting and investment power with respect to all shares shown as beneficially owned by them, subject to applicable community property laws.

  58. Additional Requirements

    (6)Consists of (i) 8,673 shares of common stock directly held, (ii) 13,291 shares of common stock held by The Bradbury Family Trust. (iii) 49,921 shares of common stock issuable upon the exercise of stock options that are exercisable or will be exercisable or RSUs settleable within 60 days of March 20, 2026. Mr. Bradbury and his spouse are trustees of The Bradbury Family Trust and their children are beneficiaries. (7)Consists of (i) 22,454 shares of common stock and (ii) 13,012 shares of common stock issuable upon the exercise of stock options that are exercisable or will be exercisable or RSUs settleable within 60 days of March 20, 2026. (8)Consists of (i) 19,309 shares of common stock and (ii) 69,921 shares of common stock issuable upon the exercise of stock options that are exercisable or will be exercisable or RSUs settleable within 60 days of March 20, 2026. (9)Consists of (i) 14,002 shares of common stock and (ii) 5,329 shares of common stock issuable upon the exercise of stock options that are exercisable or will be exercisable or RSUs settleable within 60 days of March 20, 2026. (10)Consists of (i) 27,254 shares of common stock and (ii) 13,012 shares of common stock issuable upon the exercise of stock options that are exercisable or will be exercisable or RSUs settleable within 60 days of March 20, 2026. (11)Consists of (i) 21,964 shares of common stock and (ii) 35,026 shares of common stock issuable upon the exercise of stock options that are exercisable or will be exercisable or RSUs settleable within 60 days of March 20, 2026. (12)Consists of (i) 25,906 shares of common stock and (ii) 16,962 shares of common stock issuable upon the exercise of stock options that are exercisable or will be exercisable or RSUs settleable within 60 days of March 20, 2026. (13)Consists of (i) 21,479 shares of common stock held by Derek J. Maetzold, (ii) 51,566 shares of common stock held by The Maetzold Descendants 2020 Trust, (iii) 43,826 shares of common stock held by The Derek Maetzold 2020 Irrevocable Trust, (iv) 3,336 shares of common stock held by The Maetzold 2018 Remainder Trust FBO Emily Carol Kirk, (v) 3,336 shares of common stock held by The Maetzold 2018 Remainder Trust FBO Hannah Elizabeth Maetzold, (vi) 3,336 shares of common stock held by The Maetzold 2018 Remainder Trust FBO John Derek Maetzold, (vii) 3,336 shares of common stock held by The Maetzold 2018 Remainder Trust FBO Peter Douglas Maetzold, (viii) 85,959 shares of common stock held by DJM Grantor Retained Annuity Trust No. 5, (ix) 18,718 shares of common stock held by DJM Grantor Retained Annuity Trust No. 6, (x) 44,323 shares of common stock held by DJM Grantor Retained Annuity Trust No. 7, and (xi) 541,826 shares of common stock issuable upon the exercise of stock options that are exercisable or will be exercisable within 60 days of March 20, 2026. Mr. Maetzold is trustee and beneficiary of the DJM Grantor Retained Annuity Trust No. 5 and 7. Mr. Maetzold’s spouse is trustee of The Maetzold Descendants 2020 Trust, and Mr. Maetzold’s spouse and their children are beneficiaries. Mr. Maetzold is trustee of the Derek Maetzold 2020 Irrevocable Trust and his children are beneficiaries. Mr. Maetzold is trustee of The Maetzold 2018 Remainder Trust FBO Hannah Elizabeth Maetzold, The Maetzold 2018 Remainder Trust FBO Peter Douglas Maetzold, The Maetzold 2018 Remainder Trust FBO Emily Carol Kirk and The Maetzold 2018 Remainder Trust FBO John Derek Maetzold (collectively the “Children’s Trusts”) and his children are beneficiaries. Mr. Maetzold is trustee of the DJM Grantor Retained Annuity Trust No. 6 and the beneficiaries are the Children’s Trusts. (14)Consists of (i) 60,085 shares of common stock and (ii) 168,599 shares of common stock issuable upon the exercise of stock options that are exercisable or will be exercisable within 60 days of March 20, 2026. (15)Consists of (i) 39,047 shares of common stock held by Kristen M. Oelschlager, (ii) 97,251 shares of common stock held by The Fritz Shorter Trust and (iii) 153,160 shares of common stock issuable upon the exercise of stock options that are exercisable or will be exercisable within 60 days of March 20, 2026. Kristen M. Oelschlager and her spouse are trustees and beneficiaries of the Fritz Shorter Trust. (16)Consists of (i) 86,825 shares of common stock and (ii) 147,760 shares of common stock issuable upon the exercise of stock options that are exercisable or will be exercisable within 60 days of March 20, 2026. (17)Consists of the shares described in footnotes (6) through (16).

  59. EXECUTIVE COMPENSATION PHILOSOPHY AND OBJECTIVES

    EXECUTIVE COMPENSATION PHILOSOPHY AND OBJECTIVES We have designed our executive compensation program to attract, retain, and motivate our executive officers, including our NEOs, by offering competitive compensation packages consisting of a base salary, an annual cash bonus, and long-term equity incentive awards, at a level consistent with market trends and industry data that we believe allows us to compete for the best talent in the highly-competitive environment in which we operate. We believe the approach that has been adopted by our Compensation Committee, which includes regular stockholder outreach and consideration of the feedback we receive, with its emphasis on variable cash compensation, time-based equity awards, and performance-based equity awards, enables us to attract top talent, motivate successful short-term and long-term performance, satisfy our retention objectives, and align the compensation of our executive officers with our performance and long-term value creation for our stockholders.

  60. SUMMARY OF OUR EXECUTIVE COMPENSATION PROGRAM

    SUMMARY OF OUR EXECUTIVE COMPENSATION PROGRAM Our executive compensation program is designed to compensate our executive officers competitively based upon an assessment of compensation available in the marketplace where we compete for executive talent and our desire to achieve a balance of short-term and long-term rewards for maintaining and improving Company performance and stockholder value. It is administered by our Compensation Committee. We believe our executive compensation program has assisted us in achieving strong performance for our customers, employees and stockholders. For example, during 2025, we generated total annual revenues of $344.2 million, exceeding the target level of $301.0 million established under our 2025 annual cash bonus program. See “Annual Performance-Based Cash Bonuses” below for more information. We are strongly committed to a pay-for-performance culture which includes using cash incentives to reward in-year execution as well as long-term incentives that increase in value as the stock price improves. For 2025, 52% of our CEO’s total compensation was tied to performance via cash incentives and performance-based equity awards. We compete for talent in a highly competitive industry that requires specific expertise to innovate, test and gain approval for our products in a safe manner for patients. Our compensation policies seek to balance near-term execution with long-term performance to ensure appropriate risk taking given the highly regulated industry we operate within. Our approach to establishing executive compensation is to examine a variety of factors including market data, experience, role, history, internal pay parity, affordability and individual performance. Market-based ranges for each position, and an executive officer's positioning within that range, inform the Compensation Committee's determination of overall compensation within a competitive market range. The material elements of our executive compensation program include: •Base salary, which provides a stable means of cash compensation designed to provide competitive compensation that reflects the contributions and skill levels of each executive officer. •Short-term incentive compensation, consisting of our annual cash bonus program, under which our CEO’s payout is based entirely on the achievement of pre-established corporate performance goals and our other NEOs’ payouts are based on the achievement of pre-established corporate performance goals and individual performance. This program is designed to encourage and reward the accomplishment of goals that advance the interests of the Company and its stockholders and to create alignment and focus across the organization. •Long-term incentive compensation, consisting of a mix of stock-based awards designed to reward sustained performance and align a meaningful portion of executive compensation more directly with long-term stockholder value creation. Our executive compensation program is designed to link a significant portion of the compensation of our executive officers to defined performance objectives that we believe properly incentivize our executive officers to strive for near-term earnings and returns as well as growth in long-term stockholder value. Since 2022, our executive officers’ annual equity awards have consisted of RSUs and PSUs, with PSUs representing 50% of our

  61. 2025 STOCKHOLDER OUTREACH

    2025 STOCKHOLDER OUTREACH We believe that active and transparent engagement with our stockholders is fundamental to our commitment to delivering sustainable long-term value. Each year, we proactively seek engagement with our top 25 stockholders. In 2025, our outreach efforts resulted in select members of our Board and management meeting with stockholders representing approximately 20% of our outstanding shares. Our 2025 engagement discussions included feedback on our executive compensation program. Stockholders generally expressed support for the overall structure and alignment of our compensation framework with performance and long-term value creation. More specifically, stockholders indicated that the structure provided a clear framework for short-term incentives and strong alignment with performance. Further, the addition of performance stock units was viewed favorably as an enhancement to our long-term incentive design. Feedback from these engagements is reviewed by management and our Board. Stockholder input has informed ongoing enhancements to our executive compensation program, including continued emphasis on performance-based, long-term incentives aligned with stockholder interests and key operating and financial metrics. We remain committed to maintaining open lines of communication with our stockholders and incorporating constructive feedback into our policies, practices, and strategic priorities.

  62. COMPENSATION COMMITTEE OVERSIGHT OF COMPENSATION-RELATED RISKS

    | What We Do | | | | Pay-for-Performance Philosophy and Culture. Our executive compensation program is designed to align incentive-based compensation with Company performance. | | | Significant Portion of “At-Risk” Executive Compensation is Performance-Based. Under our executive compensation program for 2025, 52% of the CEO’s, and, on average, 31% of our other NEOs’, total compensation as reported in the Summary Compensation Table consisted of performance-based cash bonuses and performance-vesting equity awards and was therefore “at risk,” which we believe aligns their short- and long-term interests with of those of our stockholders. | | | Independent Compensation Committee. The Compensation Committee is comprised solely of non-employee directors who satisfy applicable Nasdaq and SEC independence requirements. | | | Independent Compensation Consultant Reports Directly to the Compensation Committee. The Compensation Committee engages its own compensation consultant to assist with making compensation decisions. | | | Stock Ownership Guidelines for Directors and Officers. We maintain Stock Ownership Guidelines that require minimum ownership of our common stock by our directors, CEO and other Section 16 officers. See “Other Compensation Policies and Practices—Stock Ownership Guidelines” below for more information. | | | Multi-Year Vesting Requirements for Retention and Long- and Short-Term Alignment. The equity awards granted to our executive officers generally vest over multiple years, consistent with current market practice and our retention objectives. | | | Annual Say-On-Pay Vote. We hold an annual Say-on-Pay vote to allow our stockholders to approve, on an advisory basis, the compensation of our NEOs. | | | Active Stockholder Outreach. We proactively engage with our stockholders throughout the year. | | | Clawback Policy. Our Clawback Policy enables us to recover any incentive compensation granted, vested or paid to an executive officer during the three (3) completed fiscal years immediately preceding the date we are required to prepare an accounting restatement. Our Clawback Policy complies with Nasdaq listing standards. See “Other Compensation Policies and Practices—Clawback Policy” below for more information. | | | Prohibit Hedging or Pledging. Our insider trading policy prohibits our employees (including executive officers) and directors from engaging in hedging or short-term speculative transactions involving our securities. See “Other Compensation Policies and Practices—Prohibition on Hedging, Short Sales and Pledging” below for more information. | | | Minimize Inappropriate Risk Taking. Our executive compensation program is generally weighted toward long-term incentive compensation to discourage short-term risk taking, and includes goals that are quantifiable with objective criteria, multiple performance measures and caps on short-term incentive compensation. | | | Competitive Peer Group. Our Compensation Committee selects our peers from publicly traded biotechnology companies that have a comparable market capitalization, revenue, headcount, and research focus. |

  63. Role of Independent Compensation Consultant

    Role of Independent Compensation Consultant The Compensation Committee retains an independent compensation consultant to provide professional expertise regarding a variety of executive compensation and market practices. The independent consultant assists the

  64. Role of Independent Compensation Consultant

    | Castle Biosciences 2026 Proxy Statement | 53 |

  65. Role of Independent Compensation Consultant

    | Compensation Discussion and Analysis | Table of Contents |

  66. Role of Independent Compensation Consultant

    Compensation Committee in setting compensation and designing a comprehensive plan. In 2025, the Compensation Committee retained AON’s Talent Solutions Practice, a division of AON plc (“AON”), as its independent compensation consultant to assist it with, among other things. •Reviewing and modifying the compensation peer group; •Providing executive and director market pay analysis to inform policy direction; •Developing executive and director pay programs; •Evaluating equity pay market trends and dilution; •Providing support with stockholder outreach; •Making recommendations with respect to change in control and severance arrangements; and •Reviewing certain proxy disclosures, including this CD&A. The Compensation Committee annually evaluates the independent compensation consultant’s independence and performance under the applicable SEC and Nasdaq listing standards. The Compensation Committee believes that working with an independent compensation consultant furthers our objectives to recruit and retain qualified executives, align their interests with those of our stockholders and ensure that their compensation packages will appropriately motivate and reward ongoing achievement of our corporate objectives. The Compensation Committee conducted a specific review of its relationship with AON in 2025, pursuant to applicable SEC rules and Nasdaq listing standards, and concluded that AON’s work for the Compensation Committee did not raise any conflicts of interest.

  67. Use of Competitive Data

    Use of Competitive Data To assess the competitiveness of our executive compensation program and compensation levels, our Compensation Committee, with the assistance of AON, examines the competitive compensation data for senior executives of our peer companies, including total compensation and each element of compensation. The Compensation Committee uses a peer group to reference recent market data and understand the marketplace. However, the Compensation Committee also recognizes the importance of considering additional factors when making compensation decisions, including individual performance, experience, history and scope of responsibility, current market conditions and the specific needs of the business at critical points in time. The Compensation Committee uses its best business judgment in setting executive compensation and uses the market data provided by AON as a reference point, rather than in a formulaic manner. The Compensation Committee conducts an annual assessment of the peer group to ensure that it reflects Castle’s most current financial and sector-specific standing.

  68. Peer Group Selection and Market Analysis

    Peer Group Selection and Market Analysis The Compensation Committee engaged its independent compensation consultant, AON, to provide competitive compensation information, including pay levels, trends and mix, to inform the design of our 2025 executive compensation program. Working with the Compensation Committee, AON constructed a peer group for Castle for the Compensation Committee’s consideration and approval, after reviewing general industry data, industry-specific data and public available information in proxy statements and other SEC filings. The objective was to identify companies representing Castle's broad labor market for talent while maintaining comparability, having sufficient group size to avoid distortions from a single company, and ensuring sufficient and credible data are available. The peer group outlined below is a result of this work. When reviewing competitive market data, the Compensation Committee examines the range of market data but does not set a specific targeted percentile as part of its compensation philosophy. An executive's positioning against the competitive labor market is intended to reflect that executive's experience, marketability and performance over time. While the Compensation Committee uses competitive benchmarking in determining appropriate compensation ranges, the Compensation Committee generally avoids making “automatic” adjustments based solely on an employee's positioning relative to the market. The Compensation Committee believes this approach better utilizes competitive data to facilitate, rather than dictate, the Company's compensation decisions, which results in appropriate recognition of our top performers.

  69. Peer Group Selection and Market Analysis

    | 54 | Castle Biosciences 2026 Proxy Statement |

  70. Peer Group Selection and Market Analysis

    | Table of Contents | Compensation Discussion and Analysis |

  71. Peer Group Selection and Market Analysis

    Depending on whether the Company and an individual’s performance exceed the specified performance criteria, realized total compensation during any given year may be above or below the benchmark compensation levels. The amount and structure of compensation can also vary by executive due to negotiations and competitive pressures inherent in attracting and hiring experienced diagnostic managerial talent. To help attract and retain such talent, the Compensation Committee also seeks to provide an appropriate level of employee benefits comparable to those in the diagnostics industry and to publicly traded companies. Each year, AON reviews the external market data and evaluates the composition of our peer group to ensure it appropriately reflects our growth, the increase in our revenues and market capitalization and the consolidation in our industry. 2025 Peer Group In August 2024, the Compensation Committee updated the peer group for 2025. With the assistance of AON, the Compensation Committee considered companies: •in the life sciences industry (specifically molecular diagnostic companies, biotechnology and select pharmaceutical companies), health care supplies, life sciences tools, commercial biotechnology, health equipment and supplies as a reflection of the talent market; •with revenues of approximately one half (0.5x) to three point three times (3.3x) our then-projected revenue (when rounded, this resulted in a range of $150 million to $1.0 billion in revenue); and •with market value of approximately 0.35x to three times (3x) our market capitalization at the time (resulting in a range of between $200 million to $1.7 billion in market capitalization). The 2025 Peer Group consists of the 18 companies listed in the table below. At the time the Compensation Committee approved the 2025 Peer Group, we were at approximately the 25th percentile for 30-day average market capitalization against the proposed peer group, and approximately at the 63rd percentile for projected revenue with a top quartile projected growth rate. The Compensation Committee considered this a reasonable balance and a good representation of companies that were of similar scope and complexity that are aligned with the potential growth of the Company. The companies comprising the 2025 Peer Group recommended by Aon and approved by the Compensation Committee are listed below:

  72. Peer Group Selection and Market Analysis

    | • Adaptive Biotechnologies Corporation (ADPT) | • GeneDx Holdings Corp. (WGS) | • OraSure Technologies, Inc. (OSUR) | | • ADMA Biologics, Inc. (ADMA) | • Guardant Health, Inc. (GH) | • Pacific Biosciences of California, Inc. (PACB) | | • Axonics, Inc. (AXNX) | • iRhythm Technologies, Inc. (IRTC) | • Quanterix Corporation (QTRX) | | • BioCryst Pharmaceuticals, Inc. (BCRX) | • Maravai LifeSciences Holdings, Inc. (MRVI) | • Silk Road Medical, Inc. (SILK) | | • CareDx, Inc. (CDNA) | • Mesa Laboratories, Inc. (MLAB) | • Twist Bioscience Corporation (TWST) | | • Cytek Biosciences, Inc. (CTKB) | • NeoGenomics, Inc. (NEO) | • Veracyte, Inc. (VCYT) |

  73. Peer Group Selection and Market Analysis

    | Castle Biosciences 2026 Proxy Statement | 55 |

  74. Peer Group Selection and Market Analysis

    | Compensation Discussion and Analysis | Table of Contents |

  75. Peer Group Selection and Market Analysis

    Changes from Prior Peer Group(1)

  76. Peer Group Selection and Market Analysis

    | Added for 2025 | Removed for 2025 | | Cytek Biosciences, Inc. (CKTB) | Invitae Corporation (NVTAQ) | | GeneDx Holdings Corp. (WGS) | Natera, Inc. (NTRA) | | Maravai Lifesciences Holdings, Inc. (MVRVI) | |

  77. Peer Group Selection and Market Analysis

    (1)Primarily due to change in revenue, market value, and/or being acquired.

  78. Annual Performance-Based Cash Bonuses

    Annual Performance-Based Cash Bonuses Annual performance-based cash bonuses are designed to provide our NEOs with appropriate incentives to achieve pre-defined annual performance goals. Payments under our annual cash bonus program are primarily based on the achievement of corporate performance goals that are pre-established by our Board. Goals are typically approved in the first quarter and are designed to incentivize focus and strong execution on the part of the leadership team. Actual performance against these performance goals funds the annual bonus plan pool and threshold levels of performance must be met for the pool to be funded. Each of our NEOs participated in our 2025 annual cash bonus program. Executive officers who participate in this plan have a pre-established target bonus opportunity, expressed as a percentage of their base salary. In early 2025, after determining that our NEOs’ prior year target bonus opportunities remained competitive and consistent with their respective roles and responsibilities, our Compensation Committee and, with respect to our CEO, the independent members of the Board, approved the following target bonus opportunities for our NEOs for fiscal 2025. The 2025 bonus payout opportunities were capped at 138% of target for our CEO and 130% of target for our other NEOs.

  79. Annual Performance-Based Cash Bonuses

    | Named Executive Officer | 2025 Target Bonus Opportunity (As % of Base Salary) | 2025 Target Bonus Opportunity ($) | | Derek J. Maetzold | 100% | 751,350 | | Frank Stokes | 55% | 287,399 | | Tobin W. Juvenal | 55% | 291,062 | | Kristen M. Oelschlager | 55% | 291,062 |

  80. Annual Performance-Based Cash Bonuses

    Our CEO’s bonus payout is based entirely on the achievement of corporate performance goals. For the other NEOs, 80% of their bonus payout is based on the achievement of corporate performance goals, with the remaining 20% based on individual performance. The individual performance component may be adjusted upward or downward by a performance multiplier determined by the Compensation Committee, taking into consideration the CEO’s assessment. The individual performance multipliers for the other NEOs are the same as those used for all other Castle employees. Payments related to individual performance over the target level are reported as a discretionary bonus, as discussed further below. The Compensation Committee used a sliding scale of revenue performance ranging from $279.0 million to $331.0 million to determine the actual weighting, as detailed below. The Compensation Committee used a sliding scale rather than a fixed threshold to better align the actual bonus payouts to the actual level of revenues, given the wide range of possible results. In setting this performance range, the Compensation Committee considered the loss of Medicare coverage for our DecisionDx-SCC test, effective April 24, 2025, which had an adverse impact on our 2025 revenue. The actual revenue for 2025 was $344.2 million. The table below reflects the 2025 corporate performance goals for the 2025 annual bonus plan and the resulting achievement approved by the independent members of our Board in January 2026, at the recommendation of the Compensation Committee.

  81. Annual Performance-Based Cash Bonuses

    | Castle Biosciences 2026 Proxy Statement | 57 |

  82. Annual Performance-Based Cash Bonuses

    | Compensation Discussion and Analysis | Table of Contents |

  83. Annual Performance-Based Cash Bonuses

    | Goal Category | Corporate Performance Goals | Target | Actual | Target Weighting | Actual Weighting | | Revenue | Revenue for the year ended December 31, 2025 | $301.0 million | $344.2 million | 75% | 113%(1) | | Long-term Initiatives | •Completion of product updates (and acquisitions) •Identification of an electronic medical record (“EMR”) company to improve the integration of our commercial tests within their EMR system •Achievement of certain reimbursement rates for DecisionDx-SCC | •Complete two product updates (and acquisitions) •Identify an EMR company, negotiate and execute an integration agreement, and launch a technical kick-off •Achieve specified reimbursement rates | •Completed two product updates (and acquisitions), including the limited access launch of AdvanceAD-Tx and acquisition of Capsulomics •Achieved EMR company negotiations •Specified reimbursement rates achieved | 25% | 25%(2) | | | | | | 100% | 138% |

  84. Annual Performance-Based Cash Bonuses

    (1)For illustration purposes, only the minimum, actual, target, and maximum performance levels on the sliding scale of revenue performance are displayed below, along with the actual performance level.

  85. Annual Performance-Based Cash Bonuses

    | | 2025 Revenue ($ millions) | Factor for Pool Funding (A) | Target Weighting (B) | Actual Weight for Revenue Component (A x B) | | Actual | $344.2 | 150% | 75% | 113% | | Maximum | $331.0 | 150% | 75% | 113% | | Target | $301.0 | 100% | 75% | 75% | | Minimum | $279.0 | 50% | 75% | 38% |

  86. Annual Performance-Based Cash Bonuses

    (2)The actual weighting could have ranged between 0% (for below target performance of all components) and 25% (for target performance of all components). The actual outcome was based on objectively determinable information with respect to product updates (including acquisitions), identification of and integration with an EMR company, and specified reimbursement rates. No discretion was applied by the Compensation Committee. We are not disclosing the specific targets or specific actual outcomes of the reimbursement rate metric because we believe it would provide our competitors with insight into our internal confidential strategic operations and planning processes and could cause us competitive harm. The specific targets were set to be consistent with the Company’s long-term growth strategy. Achieving this level would require not only sustained organic growth but also successful execution of key strategic initiatives. Given the inherent challenges in achieving and maintaining profitability in our industry, the specific target was intentionally set at a level that demands superior execution.

  87. Annual Performance-Based Cash Bonuses

    | Milestone | Percent Range | Actual Achieved | | Complete two product updates (including acquisitions) | 0% to 10% | 10% | | Identify EMR company | 0% to 10% | 10% | | Achieve specified reimbursement rate | 0% to 5% | 5% | | | | 25% |

  88. Annual Performance-Based Cash Bonuses

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  89. Annual Performance-Based Cash Bonuses

    | Table of Contents | Compensation Discussion and Analysis |

  90. Annual Performance-Based Cash Bonuses

    The Compensation Committee selected these corporate performance goals and this incentive structure in order to measure a variety of key drivers of Castle’s performance that it expects to contribute to Castle’s long-term growth. The Compensation Committee believes that the revenue metric represents the most important of these metrics due to its importance to our financial results and its use by investors in understanding our business. Revenue also represents a culmination of our efforts across multiple initiatives, including the effectiveness of our sales and marketing efforts and achieving reimbursement milestones. Therefore, the revenue metric received the greatest weight. The individual performance of the NEOs (other than the CEO) was also certified by the Compensation Committee, after considering the CEO’s feedback, and was set at 125% of target for Mr. Stokes, Mr. Juvenal and Ms. Oelschlager. For 2025, the target payout level for the individual performance component of these NEOs’ bonus awards was 100% of target and the maximum payout level was 130% of target. These payout percentages were based on an internal performance rating assessment applied to each individual and corresponded with the approach we used internally for other employees in assessing individual performance. Target level of performance is indicative of meeting the minimum expectations for the role. The Compensation Committee determined that above target level of performance was warranted for each of these NEOs. Based on their respective performance ratings, the Compensation Committee decided to award amounts for the individual performance component of these NEOs’ bonus awards above the target level. Payments related to individual performance above the individual performance level of 100% are considered discretionary amounts. Such amounts are reported in the “Bonus” column of the Summary Compensation Table instead of the “Non-equity incentive plan compensation” column. Such incremental amount awarded to Mr. Stokes was $14,370 and Mr. Juvenal and Ms. Oelschlager were $14,553 for 2025. The calculation of our NEOs’ earned annual incentives for 2025 were as follows:

  91. Annual Performance-Based Cash Bonuses

    | Name | Base Salary ($) | Target Bonus (%) | Target Bonus ($)(1) | Corporate Performance Actual (%) | Corporate Performance Weighting (%) | Individual Performance Actual (%) | Individual Performance Weighting (%) | Actual Bonus ($)(2) | | Derek J. Maetzold | 751,350 | 100 | 751,350 | 138 | 100 | — | — | 1,036,863 | | Frank Stokes | 522,544 | 55 | 287,399 | 138 | 80 | 125 | 20 | 389,138 | | Tobin W. Juvenal | 529,204 | 55 | 291,062 | 138 | 80 | 125 | 20 | 394,098 | | Kristen M. Oelschlager | 529,204 | 55 | 291,062 | 138 | 80 | 125 | 20 | 394,098 |

  92. Annual Performance-Based Cash Bonuses

    (1)Target Bonus is calculated as Base Salary multiplied by Target Bonus (%). (2)Actual bonus is calculated as follows: (Target Bonus ($) x Corporate Performance Actual x Corporate Performance Weighting) + (Target Bonus ($) x Individual Performance Actual x Individual Performance Weighting). As a percentage of target bonus, the actual bonus amounts earned were 138% for Mr. Maetzold and 135.4% for Messrs. Stokes and Juvenal and Ms. Oelschlager.

  93. Equity-Based Incentive Awards

    Equity-Based Incentive Awards Overview We have granted and intend to continue granting equity-based incentive awards pursuant to the 2019 Plan. We believe that our ability to grant equity-based awards is a valuable and necessary compensation tool that aligns the long-term financial interest of our employees, consultants and directors with the financial interests of our stockholders. In addition, we believe that our ability to grant equity-based awards helps us to attract, retain and motivate employees, consultants and directors, and encourages them to devote their best efforts to our business and financial success. Our Compensation Committee is responsible for approving equity grants or making recommendations regarding equity grants to the Board. Vesting of equity awards is generally tied to continuous service with us and serves as an additional retention measure. Our executives generally are awarded an initial new

  94. Equity-Based Incentive Awards

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  95. Equity-Based Incentive Awards

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  96. Equity-Based Incentive Awards

    hire grant upon commencement of employment and are eligible to receive annual equity grants thereafter. The Compensation Committee determines the size and structure of annual equity awards in its discretion based on a review of various factors, including market data, peer practices, individual and business performance, and market trends provided by AON. 2025 Equity Award Mix Based on consideration of continued stockholder feedback and the recommendations of the Compensation Committee and Aon, our Board approved the following mix of long-term equity incentives for 2025: The time-based RSUs vest in annual installments over a four-year period subject to the holder’s continuous service with us. The PSUs vest contingent upon the achievement of specified financial performance measures, as described below under “2025 PSUs.” The higher proportion of time-based RSUs awarded to our non-CEO NEOs is consistent with market data for their respective positions and is intended to support retention and foster teamwork. 2025 PSUs The 2025 PSUs are tied to the Company’s cumulative revenue and adjusted EBITDA performance as measured at the end of a three-year performance period ending on December 31, 2027. The revenue and adjusted EBITDA performance metrics are equally weighted at 50%. The Compensation Committee selected revenue as a performance metric because it believes that, as an early-stage commercial company, revenue is a critically important financial measure in understanding our current business performance and assessing our future potential. The Compensation Committee also considered that revenue is a component of the annual cash bonus program and determined that, given its importance to the Company and its reflection of progress across multiple initiatives over time, including the effectiveness of our sales and marketing efforts and achieving reimbursement milestones, it was appropriate to use revenue as a performance metric for the 2025 PSUs. The Compensation Committee selected adjusted EBITDA as a performance metric because it is an important measure used by financial analysts and investors to assess our financial condition and operating performance. We calculate adjusted EBITDA as GAAP net (loss) income adjusted to exclude interest income, interest expense, income tax benefit or expense, depreciation and amortization expense, stock-based compensation expense and change in fair value of equity securities. As an example for how we have calculated adjusted EBITDA in the past, refer to our reconciliation of adjusted EBITDA for the three and twelve months ended December 31, 2025 to the most directly comparable GAAP financial measure presented within the tables at the end of our earnings release furnished as Exhibit 99.1 to our Current Report on Form 8-K filed with the U.S. Securities and Exchange Commission on February 26, 2026. We are not disclosing the specific targets of these performance metrics because we believe doing so would provide our competitors with insight into our internal confidential strategic operations and planning processes and could cause us competitive harm. We will provide threshold, target and maximum performance goals, related payout opportunities, and final performance and pay outcomes at the conclusion of the performance period.

  97. Equity-Based Incentive Awards

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  98. Equity-Based Incentive Awards

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  99. Equity-Based Incentive Awards

    Prior Year PSU Performance In December 2022, we granted PSUs which carried a two-year performance period and an additional time-based vesting component for half of any vesting awards (the “2022 PSUs”). In August 2024, the Board certified achievement of the applicable revenue goal. As a result, 50% of the 2022 PSUs vested in August 2024, and the remaining 50% vested on August 8, 2025, subject to time-based vesting and continued service. In fiscal year 2023, in order to be further aligned with our pay-for-performance philosophy and in response to stockholder feedback, the Compensation Committee decided to shift the timing of the grant of equity awards to our executive officers from the fourth quarter of our fiscal year to the first quarter of our subsequent fiscal year. Accordingly, no new awards were granted during 2023. In 2024, we granted PSUs to each of our NEOs (the “2024 PSUs”) that are tied to the Company’s revenue and adjusted EBITDA performance as measured at the end of a three-year performance period ending on December 31, 2026, as well as the commercial launch of an inflammatory skin disease test by the end of 2026 (the “ISD Milestone”). In January 2026, based on the Company’s commercial launch of our AdvanceAD-Tx test in November 2025, the Board certified achievement of the ISD Milestone. As a result, 50% of the 2024 PSUs vested in January 2026.

  100. AGREEMENTS WITH OUR NEOs

    AGREEMENTS WITH OUR NEOs Below are descriptions of our employment agreements with our NEOs. Each of our executive officers’ employment is at will and may be terminated by us at any time. Any potential payments and benefits due upon a qualifying termination of employment or a change in control are further described below under “—Potential Benefits upon Termination or Change in Control.” Mr. Maetzold. We entered into an employment agreement with Mr. Maetzold in June 2008, which was last amended in June 2019, and which governs the current terms of his employment with us. Under the terms of the employment agreement, Mr. Maetzold is entitled to an annual base salary. In addition, Mr. Maetzold is eligible to receive an annual performance cash bonus with a target payout of up to 100% of his base salary depending on corporate performance and his individual performance. Pursuant to his employment agreement, as amended, Mr. Maetzold is entitled to receive periodic grants of stock options, as determined by our Board. Mr. Stokes. We entered into an offer letter agreement with Mr. Stokes in November 2017, which governs the current terms of his employment with us. Under the terms of the employment agreement, Mr. Stokes is entitled to an annual base salary and is eligible to receive an annual performance cash bonus. Mr. Juvenal. We entered into an employment agreement with Mr. Juvenal in October 2008, which was last amended in April 2009, and which governs the current terms of his employment with us. Under the terms of the employment agreement, Mr. Juvenal is entitled to an annual base salary and is eligible to receive an annual performance cash bonus with a target payout of 50% (increased to 55% beginning in 2024) of his base salary depending on corporate performance and individual performance. Ms. Oelschlager. We entered into an employment agreement with Ms. Oelschlager in September 2008, which was last amended in April 2016, and which governs the current terms of her employment with us. Under the terms of the employment agreement, Ms. Oelschlager is entitled to an annual base salary and is eligible to receive an annual performance cash bonus with a target payout of 50% (increased to 55% beginning in 2024) of her base salary depending on corporate performance and individual performance.

  101. POTENTIAL BENEFITS UPON TERMINATION OR CHANGE IN CONTROL

    POTENTIAL BENEFITS UPON TERMINATION OR CHANGE IN CONTROL This “Potential Benefits upon Termination or Change in Control” section should be read in conjunction with the “—Potential Payments upon Termination or Change in Control” section below, which provides a table that quantifies the benefits described in this section.

  102. POTENTIAL BENEFITS UPON TERMINATION OR CHANGE IN CONTROL

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  103. POTENTIAL BENEFITS UPON TERMINATION OR CHANGE IN CONTROL

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  104. Severance and Change in Control Plan

    Severance and Change in Control Plan Regardless of the manner in which a NEO’s service terminates, each NEO is entitled to receive amounts earned during his or her term of service, including unpaid salary and any unused vacation time. In addition, each of our NEOs is eligible to receive certain benefits in connection with certain terminations pursuant to his or her participation agreement with our Severance and Change in Control Plan (the “Severance Plan”), including continuing coverage under the Consolidated Omnibus Budget Reconciliation Act of 1985 (“COBRA”). The term “change in control” has the meaning provided in the 2019 Plan, as further described below. The definitions of “covered termination” and “good reason” referenced below are in the Severance Plan filed as an exhibit to the Company’s Annual Report on Form 10-K for the fiscal year ended December 31, 2025. Mr. Maetzold. Upon Mr. Maetzold’s covered termination that does not occur during a change in control period, Mr. Maetzold will be eligible to receive (i) continued base salary for 18 months, to be paid in accordance with our normal payroll procedures and less any applicable withholdings, (ii) a cash bonus equal to 150% of the greater of the most recent annual performance bonus target or actual bonus earned, to be paid in equal regular installments over 18 months in accordance with our normal payroll procedures and less any applicable withholdings, (iii) continuation of coverage under COBRA at our expense for up to 18 months, (iv) 18 months’ acceleration on the vesting of any unvested portion of outstanding time-vesting equity awards, and (v) a prorated number of shares underlying performance-based awards determined based on the number of days from the start of the performance period until the covered termination, divided by the total performance period, with the number of shares determined based on actual performance as of the end of the relevant performance period. In the event Mr. Maetzold’s covered terminated occurs during a change in control period (beginning three months before, and ending 12 months following a change in control), he will be eligible to receive (i) continued base salary for 36 months, payable in a lump sum after the date of termination less any applicable withholdings, (ii) a cash bonus equal to 300% of annual performance bonus target for the year in which the event occurs, to be paid in a lump sum after the date of termination, (iii) continuation of coverage under COBRA at our expense for up to three years, and (iv) immediate vesting of any unvested portion of time-vesting equity awards outstanding and any performance-vesting award will accelerate vesting at 100% of the target level of performance as of the date of covered termination. In addition, if Mr. Maetzold resigns without “good reason” then he will be entitled to 12 months of continued payments of his base salary. In all events of termination, Mr. Maetzold will be paid for any unused earned vacation time. In connection with a change in control, if (i) the successor or acquiring entity does not assume or continue Mr. Maetzold’s equity awards, and (ii) he continues to be employed through the effective date of the change in control, then all his unvested and outstanding equity awards will vest, and any performance-vesting award will accelerate vesting at 100% of the target level of performance or, if greater, based on actual performance measured as of the effective time of the change in control. Mr. Stokes. Upon Mr. Stokes’ covered termination during a non-change in control period, he will be eligible to receive (i) continued base salary for 12 months, to be paid in accordance with our normal payroll procedures and less any applicable withholdings, (ii) a cash bonus equal to the annual target bonus for the current year, (iii) continuation of coverage under COBRA at our expense during such 12 month period, (iv) 12 months’ accelerated vesting of any unvested portion of outstanding time-vesting equity awards, and (v) a prorated number of shares underlying performance-based awards determined based on the number of days from the start of the performance period until the covered termination, divided by the total performance period, with the number of shares determined based on actual performance as of the end of the relevant performance period. In the event Mr. Stokes’ covered termination occurs during a change of control period, he will be eligible to receive (i) continued base salary for 12 months, payable in a lump sum after the date of termination less any applicable withholdings, (ii) a cash bonus equal to the annual bonus earned for the prior year, to be paid in a lump sum after the date of termination, (iii) continuation of coverage under COBRA at our expense during such 12 month period, and (iv) immediate vesting of any unvested portion of time-vesting equity awards outstanding and any performance-vesting award will accelerate vesting at 100% of the target level of performance as of the date of covered termination. In all events of termination, Mr. Stokes will be paid for any unused earned vacation time. In connection with a change in control, if (i) the successor or acquiring entity does not assume or continue Mr. Stokes’ equity awards, and (ii) he continues to be employed through the effective date of the change in control, then all his unvested and outstanding equity awards will vest, and any performance-vesting award will accelerate

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  107. Severance and Change in Control Plan

    vesting at 100% of the target level of performance or, if greater, based on actual performance measured as of the effective time of the change in control. Mr. Juvenal. Upon Mr. Juvenal’s covered termination during a non-change in control period, he will be eligible to receive (i) continued base salary for 12 months, to be paid in accordance with our normal payroll procedures and less any applicable withholdings, (ii) a cash bonus equal to the annual target bonus for the current year, (iii) continuation of coverage under COBRA at our expense during such 12 month period, (iv) 12 months’ accelerated vesting of any unvested portion of outstanding time-vesting equity awards, and (v) a prorated number of shares underlying performance-based awards determined based on the number of days from the start of the performance period until the covered termination, divided by the total performance period, with the number of shares determined based on actual performance as of the end of the relevant performance period. In the event Mr. Juvenal’s covered termination occurs during a change of control period, he will be eligible to receive (i) continued base salary for 12 months, payable in a lump sum after the date of termination less any applicable withholdings, (ii) a cash bonus equal to the annual bonus earned for the prior year, to be paid in a lump sum after the date of termination, (iii) continuation of coverage under COBRA at our expense during such 12 month period, and (iv) immediate vesting of any unvested portion of time-vesting equity awards outstanding and any performance-vesting award will accelerate vesting at 100% of the target level of performance as of the date of covered termination. In all events of termination, Mr. Juvenal will be paid for any unused earned vacation time. In connection with a change in control, if (i) the successor or acquiring entity does not assume or continue Mr. Juvenal’s equity awards, and (ii) he continues to be employed through the effective date of the change in control, then all his unvested and outstanding equity awards will vest, and any performance-vesting award will accelerate vesting at 100% of the target level of performance or, if greater, based on actual performance measured as of the effective time of the change in control. Ms. Oelschlager. Upon Ms. Oelschlager’s covered termination during a non-change in control period, she will be eligible to receive (i) continued base salary for 12 months, to be paid in accordance with our normal payroll procedures and less any applicable withholdings, (ii) a cash bonus equal to the annual target bonus for the current year, (iii) continuation of coverage under COBRA at our expense during such 12 month period, (iv) 12 months’ accelerated vesting of any unvested portion of outstanding time-vesting equity awards, and (v) a prorated number of shares underlying performance-based awards determined based on the number of days from the start of the performance period until the covered termination, divided by the total performance period, with the number of shares determined based on actual performance as of the end of the relevant performance period. In the event Ms. Oelschlager’s covered termination occurs during a change of control period, she will be eligible to receive (i) continued base salary for 12 months, payable in a lump sum after the date of termination less any applicable withholdings, (ii) a cash bonus equal to the annual bonus earned for the prior year, to be paid in a lump sum after the date of termination, (iii) continuation of coverage under COBRA at our expense during such 12 month period, and (iv) immediate vesting of any unvested portion of time-vesting equity awards outstanding and any performance-vesting award will accelerate vesting at 100% of the target level of performance as of the date of covered termination. In all events of termination, Ms. Oelschlager will be paid for any unused earned vacation time. In connection with a change in control, if (i) the successor or acquiring entity does not assume or continue Ms. Oelschlager’s equity awards, and (ii) she continues to be employed through the effective date of the change in control, then all her unvested and outstanding equity awards will vest, and any performance-vesting award will accelerate vesting at 100% of the target level of performance or, if greater, based on actual performance measured as of the effective time of the change in control. All severance benefits described above are subject to (i) the execution and effectiveness of a release of claims in favor of us and (ii) compliance with the executive’s employment agreement and employee proprietary information agreement. Each of our NEOs holds stock options, time-based RSUs and PSUs under the Castle Biosciences, Inc. 2008 Stock Plan (the “2008 Plan”), the Castle Biosciences, Inc. 2018 Equity Incentive Plan (the “2018 Plan”) and/or the 2019 Plan that were granted subject to the general terms of the applicable equity plan and the form of stock option or RSU agreement, as applicable. A description of the change in control provisions in the 2008 Plan, 2018 Plan and 2019 Plan are set forth below. Specific vesting terms of each NEO’s stock options, RSUs and PSUs are described under “—Outstanding Equity Awards at Fiscal Year End.”

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  109. Severance and Change in Control Plan

    | Compensation Discussion and Analysis | Table of Contents |

  110. PENSION BENEFITS AND NONQUALIFIED DEFERRED COMPENSATION

    PENSION BENEFITS AND NONQUALIFIED DEFERRED COMPENSATION There were no defined benefit pension or nonqualified deferred compensation plans in place for 2025. Our Board may elect to provide our officers and other employees with such benefits in the future if it determines that doing so is in our best interests.

  111. Retirement Policy

    Retirement Policy During 2022, our Board evaluated the retentive and succession planning value of a retirement policy. Following that review, in January 2023, our Board adopted a retirement policy for our employees who (i) generally are at or above the Vice President level on the date of their retirement, (ii) are at least 60 years of age and (iii) have completed at least five years of service with us. For equity awards that are subject to time-vesting, acceleration of the vesting and exercisability of any then-outstanding equity awards to the extent such awards were scheduled to vest during the vesting period following the retirement date based solely on the eligible employee’s continued employment with us, had such employee remained employed by us through such date, that portion of the then-outstanding equity award will be deemed immediately vested and exercisable as of the date immediately preceding the retirement date. For equity awards that are subject to performance-vesting, if the relevant performance conditions of any then-outstanding equity award are achieved prior to the retirement date but the award remains subject to time-vesting and is scheduled to vest during the vesting period following the retirement date based solely on the eligible employee’s continued employment with us, had such employee remained employed by the Company through such date, the earned portion of the award will be deemed immediately vested and exercisable as of the date immediately preceding the retirement date. If the relevant performance conditions of any then-outstanding

  112. Retirement Policy

    equity awards are not achieved prior to the retirement date, the award shall be treated according to their individual award agreements. The vesting periods are as follows: •CEO: 24 months, plus an additional six months for each year of service after the age of 66. •Senior Vice President and above: 18 months, plus an additional three months for each year of service after the age of 66. •Vice President and below: nine months, plus an additional three months for each year of service after the age of 66. Eligible employees will have 12 months following the retirement date to exercise the outstanding and vested time-vesting equity awards. Currently Mr. Maetzold and Mr. Juvenal meet the requirements for accelerated vesting upon retirement under the Retirement Policy. This policy was adopted to facilitate and support ongoing organizational changes as we build and scale the business for growth and to assist with succession planning activities.

  113. SUMMARY COMPENSATION TABLE

    SUMMARY COMPENSATION TABLE The following table shows compensation awarded to, paid to or earned by our NEOs during the years ended December 31, 2025, 2024, and 2023.

  114. SUMMARY COMPENSATION TABLE

    | Name and principal position | Year | Salary ($) | Bonus ($)(1) | Stock awards ($)(2) | Option awards ($)(2) | Non-equity incentive plan compensation ($)(3) | All other compensation ($)(4) | Total ($) | | Derek J. Maetzold President and CEO | 2025 | 751,350 | — | 4,977,208 | — | 1,036,863 | 21,350 | 6,786,771 | | | 2024 | 715,572 | — | 5,283,595 | — | 921,657 | 20,250 | 6,941,074 | | | 2023 | 686,400 | — | — | — | 893,350 | 26,234 | 1,605,984 | | Frank Stokes Chief Financial Officer | 2025 | 522,544 | 14,370 | 1,417,918 | — | 374,769 | 90,236 | 2,419,837 | | | 2024 | 500,042 | 13,751 | 1,379,780 | — | 338,388 | 74,563 | 2,306,524 | | | 2023 | 488,800 | 4,888 | — | — | 316,742 | 69,820 | 880,250 | | Tobin W. Juvenal Chief Commercial Officer | 2025 | 529,204 | 14,553 | 1,417,918 | — | 379,545 | 21,350 | 2,362,571 | | | 2024 | 506,415 | 13,926 | 1,563,738 | — | 342,701 | 20,150 | 2,446,930 | | | 2023 | 482,300 | 14,469 | — | — | 312,530 | 19,800 | 829,099 | | Kristen M. Oelschlager Chief Operating Officer | 2025 | 529,204 | 14,553 | 1,417,918 | — | 379,545 | 21,350 | 2,362,571 | | | 2024 | 506,415 | 13,926 | 1,563,738 | — | 342,701 | 20,150 | 2,446,931 | | | 2023 | 482,300 | 9,646 | — | — | 312,530 | 24,008 | 828,484 |

  115. SUMMARY COMPENSATION TABLE

    (1)Represents the discretionary portion, if any, of the performance-based cash bonuses earned during the year and paid subsequent to year end, as further described above under “— Annual Performance-Based Cash Bonuses.” (2)These columns set forth the aggregate grant date fair value of option awards and stock awards, without regard to forfeitures, granted during the year measured pursuant to FASB ASC 718. The valuation assumptions we used in calculating the fair value of options are set forth in Note 14 to our consolidated financial statements appearing in our Annual Report on Form 10-K for the fiscal year ended December 31, 2025. Note that the amounts reported in this column reflect the accounting value of these awards and do not correspond to the actual economic value that ultimately may be realized by our NEOs. The PSUs granted are subject to performance conditions, as defined under FASB ASC 718, and, therefore, the value at the grant date is based upon the probable outcome of such conditions, which corresponds to the single payout scenario under the terms of the PSUs. No equity was awarded in 2023. (3)Amounts reported represent performance-based cash bonuses earned during the year and paid subsequent to year end, as further described above under “—Annual Performance-Based Cash Bonuses,” excluding the discretionary portion included in the Bonus column of the table above. (4)The amount reported for Mr. Maetzold for 2025 reflects $21,000 in 401(k) matching contributions. The amount reported for Mr. Stokes for 2025 reflects expenses paid by the Company to reimburse Mr. Stokes for $42,307 of commercial air travel and parking attributable to commuting from his home in Charlotte, North Carolina to our offices in Friendswood, Texas, $22,979 for lodging, $21,000 in 401(k) matching contributions and $3,600 for the cost of vehicle lease payments. The amount reported for Mr. Juvenal for 2025 reflects $21,000 in 401(k) matching contributions and Ms. Oelschlager for 2025 reflects $21,000 in 401(k) matching contributions. Mr. Maetzold, Mr. Stokes, Mr. Juvenal and Ms. Oelschlager all received a $350 holiday gift.

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  117. SUMMARY COMPENSATION TABLE

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  118. GRANTS OF PLAN-BASED AWARDS

    GRANTS OF PLAN-BASED AWARDS The following table below shows certain information regarding grants of plan-based awards to our NEOs during the year ended December 31, 2025.

  119. GRANTS OF PLAN-BASED AWARDS

    | | | | Estimated future payouts under non-equity incentive plan awards(1) | | | Estimated future payouts under equity incentive plan awards (in shares) | | | All Other Stock Awards: Number of Shares of Stock (#) | Grant Date Fair Value of Stock Awards ($)(2) | | Name | Award Type | Grant Date | Threshold ($) | Target ($) | Maximum ($) | Threshold (#) | Target (#) | Maximum (#) | | | | Derek J. Maetzold | Cash Incentive | — | 281,756 | 751,350 | 1,036,863 | — | — | — | — | — | | | Time-based RSUs | 3/4/2025 | — | — | — | — | — | — | 111,948 | 2,488,604 | | | PSUs | 3/4/2025 | — | — | — | — | 111,948 | — | — | 2,488,604 | | Frank Stokes | Cash Incentive | — | 114,960 | 287,399 | 374,769 | — | — | — | — | — | | | Time-based RSUs | 3/4/2025 | — | — | — | — | — | — | 47,838 | 1,063,439 | | | PSUs | 3/4/2025 | — | — | — | — | 15,946 | — | — | 354,480 | | Tobin W. Juvenal | Cash Incentive | — | 116,425 | 291,062 | 379,545 | — | — | — | — | — | | | Time-based RSUs | 3/4/2025 | — | — | — | — | — | — | 47,838 | 1,063,439 | | | PSUs | 3/4/2025 | — | — | — | — | 15,946 | — | — | 354,480 | | Kristen M. Oelschlager | Cash Incentive | — | 116,425 | 291,062 | 379,545 | — | — | — | — | — | | | Time-based RSUs | 3/4/2025 | — | — | — | — | — | — | 47,838 | 1,063,439 | | | PSUs | 3/4/2025 | — | — | — | — | 15,946 | — | — | 354,480 |

  120. GRANTS OF PLAN-BASED AWARDS

    (1)The amounts reported in these columns represent the range of possible annual cash incentive amounts (at the threshold, target and maximum levels) that could have been paid to each of our NEOs for the year ended December 31, 2025, pursuant to their annual performance-based cash bonus. Each of our NEOs’ cash bonuses, other than Mr. Maetzold’s, is calculated based (i) 80% on achievement of corporate performance goals and (ii) 20% on individual performance objectives. Mr. Maetzold’s annual cash bonus is based entirely (100%) on the achievement of corporate performance goals. The amounts shown as “Threshold” reflect the payment level under the cash bonus if the corporate performance goals were achieved at the minimum level of 38% (calculated based on the specific performance objectives and each goal set at the minimum level at which a payout for performance could have been earned) and at the minimum level at which a payout for individual performance could have been earned of 50% for our NEOs other than Mr. Maetzold. The amounts shown as “Target” reflect the payment level under the cash bonus if the corporate performance goals were achieved at the target level of 100% (calculated based on the specific performance objectives and goals each set at the target level) and at the target level of individual performance of 100% for our NEOs other than Mr. Maetzold. The amounts shown as “Maximum” reflect the payment level under the cash bonus if the corporate performance goals were achieved at the maximum level of 138% (calculated based on the specific performance objectives and goals each set at the maximum level) and at the maximum level of individual performance of 130% for our NEOs other than Mr. Maetzold. Actual payouts made under the Performance-Based Bonus differed based on the actual performance objectives and goals achieved. The actual cash bonus award earned by each NEO for performance in the year ended December 31, 2025, is set forth in the “Summary Compensation Table” above. As such, the amounts set forth in these columns do not represent additional compensation earned by the NEOs for the year ended December 31, 2025. Annual performance-based cash bonuses are discussed in greater detail under the heading “Annual Performance-Based Cash Bonuses” above. (2)Amounts represent the aggregate expense to be recognized for financial statement reporting purposes in accordance with FASB ASC 718 for RSU and PSU awards granted to our NEOs. Assumptions used in the calculation of the grant date fair value of the RSUs are set forth in Note 14 to our consolidated financial statements appearing in our Annual Report on Form 10-K for the fiscal year ended December 31, 2025.

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  123. OUTSTANDING EQUITY AWARDS AT FISCAL YEAR END

    OUTSTANDING EQUITY AWARDS AT FISCAL YEAR END The following table presents information regarding outstanding equity awards held by our NEOs as of December 31, 2025.

  124. OUTSTANDING EQUITY AWARDS AT FISCAL YEAR END

    | | | Option Awards (1)(2) | | | | Stock Awards(1) | | | | | Name | Vesting Commencement Date | Number of Securities Underlying Unexercised Options (#) Exercisable | Number of Securities Underlying Unexercised Options (#) Unexercisable | Option Exercise Price ($)(3) | Option Expiration Date | Number of shares or units of stock that have not vested (#)(4) | Market value of shares or units of stock that have not vested ($)(5) | Equity incentive plan awards: number of unearned shares, units or other rights that have not vested (#)(6) | Equity incentive plan awards: market or payout value of unearned shares, units or other rights that have not vested ($)(5) | | Derek J. Maetzold | 5/10/2018 | 98,441 | — | 2.39 | 05/09/2028 | — | — | — | — | | | 11/6/2018 | 20,508 | — | 2.39 | 11/11/2028 | — | — | — | — | | | 3/13/2019 | 65,627 | — | 3.38 | 03/12/2029 | — | — | — | — | | | 12/13/2019 | 170,000 | — | 29.50 | 12/12/2029 | — | — | — | — | | | 12/10/2020 | 87,100 | — | 59.16 | 12/09/2030 | — | — | — | — | | | 12/10/2021 | 106,376 | — | 40.52 | 12/09/2031 | — | — | — | — | | | 12/9/2022 | — | — | — | — | 33,496 | 1,302,994 | — | — | | | 3/4/2024 | — | — | — | — | 93,328 | 3,630,459 | 62,218 | 2,420,280 | | | 3/4/2025 | — | — | — | — | 111,948 | 4,354,777 | 111,948 | 4,354,777 | | Frank Stokes | 12/4/2017 | 25,137 | — | 2.39 | 05/09/2028 | — | — | — | — | | | 3/13/2019 | 18,712 | — | 3.38 | 03/12/2029 | — | — | — | — | | | 12/13/2019 | 55,000 | — | 29.50 | 12/12/2029 | — | — | — | — | | | 12/10/2020 | 31,000 | — | 59.16 | 12/09/2030 | — | — | — | — | | | 12/10/2021 | 42,550 | — | 40.52 | 12/09/2031 | — | — | — | — | | | 12/9/2022 | — | — | — | — | 14,617 | 568,601 | — | — | | | 3/4/2024 | — | — | — | — | 36,558 | 1,422,106 | 8,124 | 316,024 | | | 3/4/2025 | — | — | — | — | 47,838 | 1,860,898 | 15,946 | 620,299 | | Tobin W. Juvenal | 3/13/2019 | 11,210 | — | 3.38 | 03/12/2029 | — | — | — | — | | | 12/13/2019 | 35,000 | — | 29.50 | 12/12/2029 | — | — | — | — | | | 8/4/2020 | 30,000 | — | 41.36 | 08/03/2030 | — | — | — | — | | | 12/10/2020 | 29,000 | — | 59.16 | 12/09/2030 | — | — | — | — | | | 12/10/2021 | 42,550 | — | 40.52 | 12/09/2031 | — | — | — | — | | | 12/9/2022 | — | — | — | — | 15,961 | 620,883 | — | — | | | 3/4/2024 | — | — | — | — | 41,432 | 1,611,705 | 9,207 | 358,152 | | | 3/4/2025 | — | — | — | — | 47,838 | 1,860,898 | 15,946 | 620,299 | | Kristen Oelschlager | 3/13/2019 | 16,610 | — | 3.38 | 03/12/2029 | — | — | — | — | | | 12/13/2019 | 35,000 | — | 29.50 | 12/12/2029 | — | — | — | — | | | 8/4/2020 | 30,000 | — | 41.36 | 08/03/2030 | — | — | — | — | | | 12/10/2020 | 29,000 | — | 59.16 | 12/09/2030 | — | — | — | — | | | 12/10/2021 | 42,550 | — | 40.52 | 12/09/2031 | — | — | — | — | | | 12/9/2022 | — | — | — | — | 15,961 | 620,883 | — | — | | | 3/4/2024 | — | — | — | — | 41,432 | 1,611,705 | 9,207 | 358,152 | | | 3/4/2025 | — | — | — | — | 47,838 | 1,860,898 | 15,946 | 620,299 |

  125. OUTSTANDING EQUITY AWARDS AT FISCAL YEAR END

    | Castle Biosciences 2026 Proxy Statement | 69 |

  126. OUTSTANDING EQUITY AWARDS AT FISCAL YEAR END

    | Executive Compensation Tables | Table of Contents |

  127. OUTSTANDING EQUITY AWARDS AT FISCAL YEAR END

    (1)All of the option awards were granted under either the 2008 Plan, the 2018 Plan or the 2019 Plan and all of the stock awards were granted under the 2019 Plan. Additional information on our equity plans is set forth in Note 14 to our consolidated financial statements appearing in our Annual Report on Form 10-K for the fiscal year ended December 31, 2025 (2)Except for the options to purchase 65,627 shares of common stock granted to Mr. Maetzold with a vesting commencement date of March 13, 2019, which were fully vested upon issuance, each option award vests as follows: 25% of the shares subject to the option vest on the first anniversary of the vesting commencement date, and the balance of the shares vest in equal monthly installments thereafter over the next 36 months, provided in each case that the holder is then providing services to us in accordance with the terms of the 2008 Plan, the 2018 Plan or the 2019 Plan, as applicable. Certain option awards are subject to acceleration of vesting, as described under “—Potential Benefits upon Termination or Change in Control.” (3)Unless otherwise indicated, all of the option awards were granted with a per share exercise price equal to the fair market value of one share of our common stock on the date of grant. Prior to the IPO, the fair market value of our common stock was determined in good faith by our board of directors. Following the IPO, the fair market value of our common stock is the closing selling price per share of our common stock as reported on Nasdaq on the date of grant or other relevant determination date. (4)This column consists of time-based RSUs, which vest in four equal annual installments beginning on the first anniversary of the vesting commencement date. (5)Calculated using a price of $38.90 per share, which was the closing price of our common stock as reported on the Nasdaq on December 31, 2025, the last trading day of 2025. With respect to the PSUs discussed in footnote (6), the amounts shown in this column reflect the single payout scenario for the awards. (6)This column consists of PSUs granted in March 2024 and March 2025. The 2025 PSUs vest based on the Company’s revenue and adjusted EBITDA performance against pre-established performance targets as measured at the end of a three-year performance period ending on December 31, 2027. The PSUs provide for a single payout scenario, which is used as the basis for the presentation of the PSUs in the table above. We did not engage in any repricing or other modifications or cancellations to any of our NEOs’ outstanding equity awards during the fiscal year ended December 31, 2025.

  128. OUTSTANDING EQUITY AWARDS AT FISCAL YEAR END

    | 70 | Castle Biosciences 2026 Proxy Statement |

  129. OUTSTANDING EQUITY AWARDS AT FISCAL YEAR END

    | Table of Contents | Executive Compensation Tables |

  130. OPTION EXERCISES AND STOCK VESTED IN 2025

    OPTION EXERCISES AND STOCK VESTED IN 2025 The following table sets forth information regarding exercises of stock options and vesting of stock awards, which includes RSUs and PSUs, and the value realized by our NEOs during the year ended December 31, 2025.

  131. OPTION EXERCISES AND STOCK VESTED IN 2025

    | | Option Awards | | Stock Awards | | | Name | Number of shares acquired on exercise (#) | Value realized on exercise ($)(1) | Number of shares acquired on vesting (#) | Value realized on vesting ($)(2) | | Derek J. Maetzold | — | — | 147,019 | 3,856,103 | | Frank Stokes | — | — | 42,716 | 1,253,184 | | Tobin W. Juvenal | 5,393 | 173,640 | 46,582 | 1,358,101 | | Kristen M. Oelschlager | — | — | 46,582 | 1,358,101 |

  132. OPTION EXERCISES AND STOCK VESTED IN 2025

    (1)Calculated based on the difference between the exercise price of each option exercised and the closing price of our common stock on the date of exercise multiplied by the number of shares underlying each option exercised and does not represent actual amounts received by the NEOs as a result of the option exercises. (2)Calculated based on the closing price of our common stock on the vesting date multiplied by the number of shares underlying each award vested.

  133. POTENTIAL PAYMENTS UPON TERMINATION OR CHANGE IN CONTROL

    POTENTIAL PAYMENTS UPON TERMINATION OR CHANGE IN CONTROL The following table describes the potential payments and benefits to which the NEOs would have been entitled assuming an eligible termination of employment or change of control occurred on December 31, 2025, the last business day of fiscal 2025. The amounts shown are estimates and do not necessarily reflect the actual amounts that these individuals would receive on termination of employment. For further information regarding the following table, see the “—Potential Benefits upon Termination of Change in Control” section of the Compensation Discussion and Analysis in this Proxy Statement. The amounts shown in the table do not include payments and benefits to the extent they are provided generally to all salaried employees upon termination of employment and do not discriminate in scope, terms or operation in favor of the NEOs. These include accrued but unpaid salary and distributions of vested plan balances under our 401(k) plan.

  134. POTENTIAL PAYMENTS UPON TERMINATION OR CHANGE IN CONTROL

    | Castle Biosciences 2026 Proxy Statement | 71 |

  135. POTENTIAL PAYMENTS UPON TERMINATION OR CHANGE IN CONTROL

    | Executive Compensation Tables | Table of Contents |

  136. POTENTIAL PAYMENTS UPON TERMINATION OR CHANGE IN CONTROL

    | Name | Retirement ($) | Resignation Without Good Reason ($) | Change in Control Covered Period; Termination Without Cause; Resignation With Good Reason ($) | Non-Change in Control Covered Period; Termination Without Cause; Resignation With Good Reason ($) | | Derek J. Maetzold | | | | | | Salary severance | — | 751,351 | 2,254,050 | 1,127,026 | | Bonus severance | — | — | 2,254,050 | 1,127,026 | | Vacation payout | — | 624,307 | 624,307 | 624,307 | | COBRA payments | — | — | 46,964 | 23,482 | | RSU acceleration(1) | 5,900,702 | — | 9,288,231 | 5,900,702 | | Performance-vesting award acceleration(1) | — | — | 6,775,057(2) | 2,685,377(3) | | Total Estimated Value | 5,900,702 | 1,375,658 | 21,242,659 | 11,487,920 | | Frank Stokes | | | | | | Salary severance | — | — | 522,544 | 522,544 | | Bonus severance | — | — | 352,140 | 287,399 | | Vacation payout | — | 292,921 | 292,921 | 292,921 | | COBRA payments | — | — | 22,187 | 22,187 | | RSU acceleration(1) | — | — | 3,851,606 | 1,623,375 | | Performance-vesting award acceleration(1) | — | — | 936,323(2) | 364,931(3) | | Total Estimated Value | — | 292,921 | 5,977,721 | 3,113,357 | | Tobin W. Juvenal | | | | | | Salary severance | — | — | 529,204 | 529,204 | | Bonus severance | — | — | 356,628 | 291,062 | | Vacation payout | — | 401,694 | 401,694 | 401,694 | | COBRA payments | — | — | 15,433 | 15,433 | | RSU acceleration(1) | 2,625,789 | — | 4,093,486 | 1,623,375 | | Performance-vesting award acceleration(1) | — | — | 978,452(2) | 390,711(3) | | Total Estimated Value | 2,625,789 | 401,694 | 6,374,897 | 3,251,479 | | Kristen M. Oelschlager | | | | | | Salary severance | — | — | 529,204 | 529,204 | | Bonus severance | — | — | 356,628 | 291,062 | | Vacation payout | — | 333,772 | 333,772 | 333,772 | | COBRA payments | — | — | 22,187 | 22,187 | | RSU acceleration(1) | | — | 4,093,486 | 1,623,375 | | Performance-vesting award acceleration(1) | — | — | 978,452(2) | 390,711(3) | | Total Estimated Value | — | 333,772 | 6,313,729 | 3,190,311 |

  137. POTENTIAL PAYMENTS UPON TERMINATION OR CHANGE IN CONTROL

    (1)For each of the applicable outstanding unvested equity award, the dollar amount is calculated as the closing price of our common stock on December 31, 2025 ($38.90 per share) multiplied by the number of RSUs or PSUs expected to have their vesting accelerated.

  138. POTENTIAL PAYMENTS UPON TERMINATION OR CHANGE IN CONTROL

    | 72 | Castle Biosciences 2026 Proxy Statement |

  139. POTENTIAL PAYMENTS UPON TERMINATION OR CHANGE IN CONTROL

    | Table of Contents | Executive Compensation Tables |

  140. POTENTIAL PAYMENTS UPON TERMINATION OR CHANGE IN CONTROL

    (2)In connection with a change in control, any performance-vesting award will accelerate vesting at 100% of the target level of performance as of the date of covered termination. (3)In connection with a non-change in control, a prorated number of shares underlying performance-based awards; determined based on the number of days from the start of the performance period until the covered termination, divided by the total performance period, with the number of shares determined based on actual performance as of the end of the relevant performance period. The amount shown assumes that the “target” number of shares underlying performance-based awards were earned at the end of the relevant performance period and reports the prorated portion payable for a covered termination on December 31, 2025.

  141. POTENTIAL PAYMENTS UPON TERMINATION OR CHANGE IN CONTROL

    | Castle Biosciences 2026 Proxy Statement | 73 |

  142. POTENTIAL PAYMENTS UPON TERMINATION OR CHANGE IN CONTROL

    | CEO Pay Ratio |

  143. POTENTIAL PAYMENTS UPON TERMINATION OR CHANGE IN CONTROL

    As required by Section 953(b) of the Dodd-Frank Act, and Item 402(u) of Regulation S‑K, we are providing the following information about the relationship of the annual total compensation of Derek Maetzold, our CEO, and the median annual total compensation of our employees during fiscal year 2025. We believe that the pay ratio included in this information is a reasonable estimate calculated in a manner consistent with Item 402(u) of Regulation S-K. We identified our median employee as of December 31, 2025 based on our entire U.S. workforce of 882 employees after excluding our CEO. As permitted under SEC rules, for purposes of identifying our median employee, we excluded our only non-U.S. employee, or approximately 0.001% of our total employee population. To identify the median employee, we considered gross compensation totals for the year ended December 31, 2025 as our consistently applied measure of compensation. Gross compensation is calculated as the sum of regular salary or wages, bonuses paid and the grant date fair value of equity awards. We annualized salaries for hires made during the year. After identifying the median employee, we calculated the median employee’s compensation in accordance with the requirements of Item 402(c)(2)(x) of Regulation S-K applicable to the Summary Compensation Table in this Proxy Statement. Our CEO had annual total compensation in 2025 of $6,786,771 and our Median Employee had annual total compensation of $130,759. Therefore, we estimate that our CEO’s annual total compensation in 2025 was approximately 52 times that of the median of the annual total compensation of all of our employees. Because the SEC rules for identifying the median compensated employee and calculating the pay ratio based on that employee’s annual total compensation allow companies to adopt a variety of methodologies, to apply certain exclusions, and to make reasonable estimates and assumptions that reflect their compensation practices, the pay ratio reported by other companies may not be comparable to the pay ratio reported above, as other companies may have different employment and compensation practices and may use different methodologies, exclusions, estimates and assumptions in calculating their own pay ratios.

  144. POTENTIAL PAYMENTS UPON TERMINATION OR CHANGE IN CONTROL

    | 74 | Castle Biosciences 2026 Proxy Statement |

  145. POTENTIAL PAYMENTS UPON TERMINATION OR CHANGE IN CONTROL

    | Pay Versus Performance |

  146. POTENTIAL PAYMENTS UPON TERMINATION OR CHANGE IN CONTROL

    We are required by SEC rules to disclose certain information regarding compensation paid to our NEOs. The amounts set forth below under the headings “Compensation Actually Paid to PEO” and “Average Compensation Actually Paid to Non-PEO NEOs” have been calculated in a manner consistent with Item 402(v) of Regulation S-K. Footnote (2) below sets forth the adjustments from the Total Compensation for each NEO reported in the Summary Compensation Table for the relevant year.

  147. POTENTIAL PAYMENTS UPON TERMINATION OR CHANGE IN CONTROL

    | | Summary Compensation Table Total for PEO ($)(1) | Compensation Actually Paid to PEO ($)(2) | Average Summary Compensation Table Total for Non-PEO NEOs ($)(1) | Average Compensation Actually Paid to Non-PEO NEOs ($)(2) | Value of Initial Fixed $100 Investment Based on: | | | | | Year | | | | | Total Shareholder Return ($)(3) | Peer Group Total Shareholder Return ($)(3) | Net Income (Loss) ($)(4) (in thousands) | Total Revenue ($)(5) (in thousands) | | (a) | (b) | (c) | (d) | (e) | (f) | (g) | (h) | (i) | | 2025 | 6,786,771 | 13,166,820 | 2,381,659 | 4,384,636 | 57.93 | 124.75 | (24,158) | 344,229 | | 2024 | 6,941,074 | 9,967,499 | 2,400,129 | 3,322,154 | 39.69 | 93.49 | 18,245 | 332,069 | | 2023 | 1,605,984 | 779,818 | 845,945 | 496,508 | 32.14 | 94.03 | (57,466) | 219,788 | | 2022 | 7,552,577 | 3,081,353 | 2,670,395 | 990,266 | 35.06 | 89.90 | (67,138) | 137,039 | | 2021 | 6,521,857 | 2,127,860 | 2,813,079 | 1,240,785 | 63.84 | 100.02 | (31,292) | 94,085 |

  148. POTENTIAL PAYMENTS UPON TERMINATION OR CHANGE IN CONTROL

    (1)Mr. Maetzold was our “PEO” for each of the years 2021 through 2025. In this disclosure, we refer to our NEOs other than Mr. Maetzold in any fiscal year as our “Other NEOs” or our “Non-PEO NEOs.” Frank Stokes, Kristen M. Oelschlager and Tobin W. Juvenal were “Other NEOs” for each of the years 2021 through 2025. The dollar amounts are the total compensation for the covered fiscal year as reported in the Summary Compensation Table pursuant to Regulation S-K, item 402(c)(2)(x), as described under “—Summary Compensation Table.” In the case of the Other NEOs, the amounts reported are an average of the total compensation for the covered fiscal years. (2)For each year, in determining both the compensation actually paid (“CAP”) for our PEO and the average CAP for our Other NEOs, we deducted or added back the following amounts from or to the total amounts of compensation reported in column (b) and column (d) for such year. Mr. Maetzold’s CAP is calculated as follows:

  149. POTENTIAL PAYMENTS UPON TERMINATION OR CHANGE IN CONTROL

    | Year | Total Compensation from Summary Compensation Table ($) | Deduct: Stock Awards Value from Summary Compensation Table ($) | Deduct: Option Awards Value from Summary Compensation Table ($) | Add: Change in Fair Value of Awards Vesting During the Year ($)* | Add: Change in Fair Value of Outstanding and Unvested Equity Awards ($)* | Add: Year-End Fair Value of Equity Awards Granted During the Year ($)* | Compensation Actually Paid ($) | | 2025 | 6,786,771 | 4,977,208 | — | 331,938 | 2,315,765 | 8,709,554 | 13,166,820 |

  150. POTENTIAL PAYMENTS UPON TERMINATION OR CHANGE IN CONTROL

    | Castle Biosciences 2026 Proxy Statement | 75 |

  151. POTENTIAL PAYMENTS UPON TERMINATION OR CHANGE IN CONTROL

    | Pay Versus Performance | Table of Contents |

  152. POTENTIAL PAYMENTS UPON TERMINATION OR CHANGE IN CONTROL

    Other NEOs average CAP are as follows:

  153. POTENTIAL PAYMENTS UPON TERMINATION OR CHANGE IN CONTROL

    | Year | Total Compensation from Summary Compensation Table ($) | Deduct: Stock Awards Value from Summary Compensation Table ($) | Deduct: Option Awards Value from Summary Compensation Table ($) | Add: Change in Fair Value of Awards Vesting During the Year ($)* | Add: Change in Fair Value of Outstanding and Unvested Equity Awards ($)* | Add: Year-End Fair Value of Equity Awards Granted During the Year ($)* | Average Compensation Actually Paid ($) | | 2025 | 2,381,659 | 1,417,918 | — | 153,659 | 786,038 | 2,481,198 | 4,384,636 |

  154. POTENTIAL PAYMENTS UPON TERMINATION OR CHANGE IN CONTROL

    *There were no other assumptions made in the valuation of equity awards that differs materially from those disclosed as of the grant date of such equity awards. (3)For each fiscal year disclosed the cumulative total shareholder return and peer group cumulative total shareholder return is calculated in the same manner as Item 201(e) of Regulation S-K assuming an initial investment of $100 on December 31, 2020. The peer group used in this calculation is the NASDAQ Biotechnology Total Return Index. (4)The dollar amounts presented are from our consolidated financial statements appearing in our Annual Report on Form 10-K for each of the reported fiscal years. (5)This is our Company-Selected Measure provided in accordance with Item 402(v)(2)(vi) of Regulation S-K. The dollar amounts presented are from our consolidated financial statements appearing in our Annual Report on Form 10-K for each of the reported fiscal years. The following chart shows the relationships between (a) the compensation actually paid to the PEO, (b) the average compensation actually paid to the Non-PEO NEOs included in the Summary Compensation Table and (c) our company-selected measure of total revenue.

  155. POTENTIAL PAYMENTS UPON TERMINATION OR CHANGE IN CONTROL

    | 76 | Castle Biosciences 2026 Proxy Statement |

  156. POTENTIAL PAYMENTS UPON TERMINATION OR CHANGE IN CONTROL

    | Table of Contents | Pay Versus Performance |

  157. POTENTIAL PAYMENTS UPON TERMINATION OR CHANGE IN CONTROL

    The following chart shows the relationships between (a) the compensation actually paid to the PEO, (b) the average compensation actually paid to the Non-PEO NEOs included in the Summary Compensation Table and (c) our total shareholder return and the peer group total shareholder return. The following chart shows the relationships between (a) the compensation actually paid to the PEO, (b) the average compensation actually paid to the Non-PEO NEOs in the Summary Compensation Table and (c) our net income (loss).

  158. POTENTIAL PAYMENTS UPON TERMINATION OR CHANGE IN CONTROL

    | Castle Biosciences 2026 Proxy Statement | 77 |

  159. POTENTIAL PAYMENTS UPON TERMINATION OR CHANGE IN CONTROL

    | Pay Versus Performance | Table of Contents |

  160. POTENTIAL PAYMENTS UPON TERMINATION OR CHANGE IN CONTROL

    The following performance measures are the Company’s most important performance measures used by us to link compensation actually paid to our NEOs for the year-end December 31, 2025. For further information regarding these performance metrics and their function in our executive compensation program, please see “Compensation Discussion and Analysis” beginning on page 48.

  161. POTENTIAL PAYMENTS UPON TERMINATION OR CHANGE IN CONTROL

    | Performance Measures | | Financial Performance Measure: | | Revenue | | Adjusted EBITDA* | | Non-financial Performance Measures: | | Reimbursement Rates for our Tests | | Pipeline Milestones |

  162. POTENTIAL PAYMENTS UPON TERMINATION OR CHANGE IN CONTROL

    *As an example for how we have calculated adjusted EBITDA in the past, refer to our reconciliation of adjusted EBITDA for the three and twelve months ended December 31, 2025 to the most directly comparable GAAP financial measure presented within the tables at the end of our earnings release furnished as Exhibit 99.1 to our Current Report on Form 8-K filed with the U.S. Securities and Exchange Commission on February 26, 2026. All information provided above under the “Pay Versus Performance” heading will not be deemed to be incorporated by reference in any filing of our company under the Securities Act of 1933, as amended, or the Securities Exchange Act of 1934, as amended, whether made before or after the date hereof and irrespective of any general incorporation language in any such filing, except to the extent the Company specifically incorporates such information by reference.

  163. Non-Employee Director Compensation Policy

    Non-Employee Director Compensation Policy

  164. Eligible Director Compensation Limit

    Eligible Director Compensation Limit Notwithstanding anything herein to the contrary, the cash compensation and equity compensation that each Eligible Director is entitled to receive under this Policy shall be subject to the limits set forth in Section 3(d) of the Plan.