Biotechnology Value Fund Group Increases Stake in Foghorn Therapeutics to 9.99%

Biotechnology Value Fund, L.P. (BVF) and its affiliated reporting persons, including Mark N. Lampert, filed an amended Schedule 13G on May 15, 2026, regarding their holdings in Foghorn Therapeutics Inc. (FHTX). As of March 31, 2026, the reporting group collectively beneficially owns 5,866,613 shares of common stock, representing a 9.99% ownership stake in the company. This total includes 24,613 shares underlying pre-funded warrants that are currently exercisable under beneficial ownership blockers. The filing highlights a complex ownership structure where BVF Partners L.P. serves as the investment manager for several funds, including BVF, BVF II, and Trading Fund OS. Individually, BVF holds 5.4% and BVF II holds 3.8%. The reporting persons also hold additional pre-funded and series warrants for over 9.7 million shares, which are currently restricted by a 9.99% blocker provision. This amendment reflects an increase in holdings compared to the previous period, where Biotechnology Value Fund II L.P. reported zero shares. The filing was made under Rule 13d-1(c), indicating a passive investment intent.