Welcome to our dedicated page for CASTLE BIOSCIENCES SEC filings (Ticker: CSTL), a comprehensive resource for investors and traders seeking official regulatory documents including 10-K annual reports, 10-Q quarterly earnings, 8-K material events, and insider trading forms.
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Designed for fundamental investors and regulatory compliance professionals, our page simplifies access to critical SEC filings. By combining real-time EDGAR feed updates, Rhea-AI's analytical insights, and historical stock performance data, we provide comprehensive visibility into CASTLE BIOSCIENCES's regulatory disclosures and financial reporting.
CASTLE BIOSCIENCES director Tiffany Olson exercised previously granted equity awards rather than trading shares on the market. On May 22, 2026, she converted 13,667 Restricted Stock Units (RSUs) into the same number of Common Stock shares at a price of $0.00 per share, reflecting compensation rather than a cash investment.
Following this RSU settlement, Olson directly holds 39,573 shares of Castle Biosciences Common Stock. The filing shows no open-market purchases or sales and no shares withheld for taxes, indicating a straightforward vesting and settlement of RSUs, each of which represents the right to receive one share of Common Stock.
Castle Biosciences director Ellen Goldberg exercised restricted stock units into common shares. On May 22, 2026, she converted 13,667 Restricted Stock Units into 13,667 shares of Common Stock at a stated price of $0.00 per share. Following this equity award conversion, she directly holds 40,921 shares of Castle Biosciences common stock. The filing shows no open-market purchases or sales, indicating a routine compensation-related share issuance rather than a discretionary trade.
Castle Biosciences director Kim Caple exercised equity awards into common stock. On May 22, 2026, Caple converted 13,667 Restricted Stock Units into 13,667 shares of Common Stock at a price of $0.00 per share, classified as a derivative exercise rather than a market purchase.
Following this transaction, Caple directly holds 36,121 shares of Common Stock. The filing shows no open-market sales or gifts, indicating a routine compensation-related equity settlement rather than a discretionary trade. Each RSU represented the right to receive one share of Common Stock.
CASTLE BIOSCIENCES INC director Rodney Cotton acquired shares through an equity award conversion. On May 22, 2026, he exercised Restricted Stock Units into 13,667 shares of Common Stock at a stated price of $0.00 per share.
Following this transaction, Cotton directly owned 32,998 shares of Common Stock. A corresponding derivative entry shows the 13,667 Restricted Stock Units converted into the same number of Common shares, leaving no RSUs from this grant outstanding.
CASTLE BIOSCIENCES INC Chief Commercial Officer Juvenal W. Tobin exercised stock options and increased his direct common share holdings. On 2026-05-21, he exercised options for 11,210 shares of common stock at an exercise price of $3.38 per share. Following this transaction, he directly holds 98,035 shares of common stock. The exercised option, which was fully vested, now has no remaining balance.
CASTLE BIOSCIENCES INC President and CEO Derek J. Maetzold reported a series of insider trades in May 2026 involving company common stock. Across several family trusts and a personal account, entities associated with him sold a net 4,172 shares in open-market transactions at prices around $20 per share.
On the same dates, he exercised stock options to acquire 550 shares at an exercise price of $2.39 per share, increasing his direct common stock holdings. Following these transactions, one direct holding account shows 21,479 shares, while certain family trusts continue to hold tens of thousands of shares. The filing notes that these sales were executed under a pre-arranged Rule 10b5-1 trading plan adopted on December 3, 2025, indicating the trades were scheduled in advance rather than timed discretionarily.
Portolan Capital Management, LLC and manager George McCabe amended a Schedule 13G reporting beneficial ownership of 1,350,283 shares of Castle Biosciences common stock as of 03/31/2026. The filing shows 4.45% ownership and indicates sole voting and dispositive power over those shares. The amendment is signed by Mr. McCabe on 05/15/2026.
Castle Biosciences, Inc. ownership disclosure: RTW Investments, LP and Roderick Wong report beneficial ownership of 2,758,335 shares, representing 9.3% of Castle Biosciences' Common Stock based on February 19, 2026 outstanding share count of 29,731,198 shares.
The filing is an amendment to a Schedule 13G and states the reported shares are directly held by RTW Funds and that the RTW Funds have the right to receive dividends or sale proceeds. Shared voting and dispositive power are reported; sole voting and dispositive power are reported as zero.
Castle Biosciences CEO Derek J. Maetzold reported a mix of stock option exercises and share sales in Castle Biosciences Inc. common stock. On May 7, 2026, he exercised options to acquire 6,214 shares at an exercise price of $2.39 per share, converting a derivative award into common stock.
The filing also shows open-market sales totaling 9,836 shares at weighted-average prices around $22.08–$22.585 per share. These sales occurred both in his direct account and through several family and estate-planning trusts, including the Maetzold 2018 remainder trusts and 2020 trusts for descendants.
Following these transactions, Maetzold directly holds 22,385 Castle Biosciences shares, while additional shares are held indirectly through multiple trusts where he or his spouse serves as trustee. A footnote states that the transactions were carried out under a pre-arranged Rule 10b5-1 trading plan adopted on December 3, 2025, indicating the trades were scheduled in advance.
Derek Maetzold filed a Form 144 reporting proposed and recent sales of Common stock in connection with transactions routed through Goldman Sachs & Co. LLC. The filing lists multiple open-market disposals, including 23,179 shares for $584,548.88 on 03/12/2026 and 18,650 shares for $482,441.93 on 03/17/2026.
The excerpt also shows prior cashless exercises and same-day sales tied to 6,764 stock options dated 11/12/2018, and numerous trust-held share dispositions across March–April 2026.