Sirenia Capital Management LP Reports New 9.9% Stake in C4 Therapeutics, Inc.

Sirenia Capital Management LP and Alex Silverstein have filed a Schedule 13G disclosing a new significant stake in C4 Therapeutics, Inc. (CCCC). As of March 31, 2026, the reporting persons beneficially own 23,505,000 shares of common stock, representing a 9.9% ownership stake in the company. This position includes 14,170,000 shares issuable upon the exercise of warrants held by the Sirenia Fund. Notably, the reported ownership percentage is limited by a 9.99% 'blocker' provision within the warrant agreements, which prevents the reporting persons from exercising warrants if it would result in exceeding that ownership threshold. Sirenia Capital Management LP serves as the investment manager for the Sirenia Fund, while Alex Silverstein is the managing member of the general partner of Sirenia. The filing indicates that the shares were acquired in the ordinary course of business and not for the purpose of influencing or changing the control of the issuer. The principal business office for the reporting persons is located in Miami Beach, Florida.