AnaptysBio Reports Post-Trial Briefing Schedule in Tesaro Lawsuit

What Happened AnaptysBio (ANAB) reported in an Item 7.01 Regulation FD disclosure that, after a July 14–17, 2026 trial in the Delaware Court of Chancery, the company and the defendants (Tesaro, Inc., TESARO Development, Ltd. and GlaxoSmithKline) submitted a Joint Stipulation on July 28, 2026 to set a post-trial briefing schedule. The Court granted that Stipulation on July 28, 2026. The underlying litigation began when AnaptysBio filed a Verified Complaint on November 20, 2025 alleging Tesaro materially breached the parties’ Collaboration and Exclusive License Agreement and that GlaxoSmithKline tortiously interfered; the case is consolidated as In re Tesaro, Inc. Litigation, C.A. No. 2025-1357-KSJM.

Key Details

• Verified Complaint filed by AnaptysBio: November 20, 2025 (alleging material breach by Tesaro and tortious interference by GSK).
• Trial dates: July 14–17, 2026 (delivered in Delaware Court of Chancery).
• Stipulation filed and granted: July 28, 2026, establishing post-trial schedule.
• Post-trial schedule: opening brief due Aug 21, 2026; defendants’ answering brief due Sept 25, 2026; company reply due Oct 9, 2026; post-trial argument scheduled Oct 20, 2026.

Why It Matters This filing sets the timeline for the next legal steps and the Court’s consideration following trial; it does not announce a judgment or settlement. For investors, the schedule gives clear dates to watch for substantive filings and the oral argument (Oct 20, 2026) that could precede a court decision affecting the Company’s rights under the Collaboration and Exclusive License Agreement. The disclosure is procedural and does not provide details on potential financial impacts.