C4 Therapeutics, Inc. filings document the regulatory record for a clinical-stage biopharmaceutical company focused on targeted protein degradation and oncology drug development. Its 8-K reports cover material agreements, including the Roche research collaboration and license agreement for degrader-antibody conjugates, clinical and regulatory disclosures, operating results, business updates, and capital-structure matters involving common stock sales arrangements.
Proxy and governance filings describe board matters, executive compensation, equity awards, shareholder voting items, and by-law provisions, including forum-selection amendments. The filing record also includes Regulation FD disclosures, clinical presentation exhibits for cemsidomide, and other material-event reports tied to the company’s pipeline, collaborations, and public-company governance.
C4 Therapeutics, Inc. director Kenneth Carl Anderson acquired 3,662 common shares on October 1, 2026, issued under the company’s Non-Employee Director Compensation Policy after he elected shares in lieu of cash compensation for director services. The reported $3.14 per-share figure is based on the issuer’s closing market price that day. His direct common-stock holdings were 75,612 shares following the transaction.
Five additional common-stock positions were reported through trusts. Anderson disclaimed beneficial ownership of those shares except to the extent of his pecuniary interest.
C4 Therapeutics, Inc. director Donna Roy Grogan acquired 4,618 shares of common stock on October 1, 2026, under the company’s Non-Employee Director Compensation Policy. She elected to receive shares in lieu of cash compensation for her director services. The reported price was $3.14 per share, based on the closing market price that day; her direct holdings following the transaction were 79,471 shares.
C4 Therapeutics, Inc. reported new biomarker findings from its cemsidomide trials in relapsed/refractory multiple myeloma (RRMM). In the Phase 1 cemsidomide-plus-dexamethasone trial, 62 heavily pre-treated patients across once-daily dose levels showed coordinated T-cell activation, including CD8+ T cells, and functional reprogramming of natural killer cells. The presentation lists investigator-assessed overall response rates of 53% at 75 µg (20 patients) and 36% at 100 µg (19 patients). Its Phase 1 safety table reports grade 4 neutropenia in 36% (26 of 73 patients).
In Phase 1b cemsidomide with elranatamab, preliminary biomarker data from the first two patients, based on available data as of June 22, 2026, showed CD8+ effector memory T-cell expansion and activation; PD-1, TIM-3 and LAG3 expression did not increase. After the first safety cohort evaluated six patients, the safety data review committee declared the 75 µg dose level safe. The trial is advancing to a 100 µg dose-escalation safety cohort and a 75 µg expansion cohort; data from all cohorts are expected in mid-2027.
The September 2026 presentation says cash runway is expected to extend to the end of 2028.
C4 Therapeutics, Inc. (CCCC) reported that Chief Financial Officer Kendra Adams had restricted stock units vest on September 18, 2026, resulting in the acquisition of 6,250 shares of Common Stock. Of these, 2,775 shares were withheld by the company to satisfy tax withholding obligations related to the RSU vesting and settlement, which is not characterized as a market sale.
An affiliate of CCCC filed a notice related to potential sales of its common stock. The filing lists up to 4,139 shares of common stock to be sold through Morgan Stanley Smith Barney LLC Executive Financial Services, with a noted date of 08/14/2026 and NASDAQ as the trading market. It also identifies restricted stock originating from issuer grants dated 02/14/2026 and 02/14/2025. In addition, the document details prior sales by Mark Mossler over the last three months, including 15,000 shares for $61,072.50 on 08/13/2026, 19,519 shares for $76,680.39 on 08/12/2026, and 9,087 shares for $35,484.74 on 05/27/2026.
Clearance Capital Holdings (symbol CCCC) filed to allow the sale of 82,563 shares of common stock through Morgan Stanley Smith Barney LLC Executive Financial Services on the NYSE. The shares, with an aggregate market value of $1,899,926.08, consist of multiple equity awards, including restricted stock and performance shares granted between February 14, 2024 and February 15, 2025.
RA Capital Management and affiliated reporting persons report their beneficial ownership in C4 Therapeutics, Inc. common stock in an amended Schedule 13G. As of June 30, 2026, they beneficially owned 11,383,696 shares of common stock, representing 9.99% of the class, with shared voting and dispositive power and no sole power.
The RA Capital Healthcare Fund directly holds 8,000,000 common shares and multiple series of warrants exercisable for additional shares. These include pre-funded, Class A, and Class B warrants, all subject to Beneficial Ownership Blockers that prevent exercises that would raise beneficial ownership above 9.99% of the outstanding common stock.
Lynx1 Capital Management LP and Weston Nichols report beneficial ownership of 15,423,691 shares of C4 Therapeutics, Inc. common stock, including 8,097,000 shares issuable upon exercise of Class A and Class B warrants. Their stake represents 9.9% of the common stock, based on 110,567,222 shares outstanding as of May 1, 2026 and assuming warrant exercise subject to a 9.99% ownership blocker. Voting and dispositive power over all reported shares is shared, with no sole power reported. The filing notes that a prior Schedule 13G in February 2026 inadvertently excluded the warrants from the beneficial ownership calculation. The Lynx1 Master Fund has the right to receive dividends and sale proceeds from the reported shares.
C4 Therapeutics, Inc. has a significant shareholder group led by Squadron Master Fund LP and related parties reporting beneficial ownership of 7,600,000 shares of common stock. This position consists of 7,200,000 shares plus 400,000 shares underlying currently exercisable long call options held by Squadron Capital Management LLC.
The reported holdings represent approximately 6.9% of C4 Therapeutics’ common stock, based on 110,567,222 shares outstanding as of May 1, 2026, plus the option shares. Voting and dispositive powers over all 7,600,000 shares are reported as shared among Squadron Master Fund LP, Squadron Capital Management LLC, and partners Matthew Sesterhenn and William Blank, who each disclaim beneficial ownership beyond their indirect roles.
Mark Mossler filed to sell 15,000 shares of Common Stock of CCCC through Morgan Stanley Smith Barney LLC Executive Financial Services on or after 08/13/2026, with an aggregate market value of $61,072.50 on NASDAQ. The shares were acquired via a stock option exercise paid in cash. Over the prior three months, Mossler reported additional Common Stock sales of 19,519 shares for $76,680.39 on 08/12/2026 and 9,087 shares for $35,484.74 on 05/27/2026.