The legal action covers investors who acquired Erasca common stock between January 14, 2025, and April 26, 2026. According to the complaint, the company allegedly misrepresented its competitive standing by improperly comparing its ERAS-0015 molecular glue to Revolution Medicines' RMC-6236. Erasca previously touted its intellectual property as a secure moat, claiming ownership of multiple patents.

However, the narrative shifted on April 27, 2026, when the company disclosed a letter from Revolution Medicines challenging the legitimacy of Erasca's patent claims and accusing the company of misappropriating trade secrets. The market turmoil intensified following the company's revelation that a patient had died following treatment with ERAS-0015. The stock plummeted $9.25, erasing $2.8 billion in market capitalization. Reed Kathrein, a partner at Hagens Berman, stated the firm is investigating whether Erasca intentionally deceived the market regarding the safety profile and patent protections of its primary oncology asset. Investors have until August 10, 2026, to file as a lead plaintiff.