secwatch.observer — SEC 8-K summary
======================================

Issuer:     ANAPTYSBIO, INC (ANAB)
CIK:        0001370053
Form:       8-K
Filed at:   2025-11-26T23:59:59+00:00
Accession:  0001370053-25-000103
Event type: litigation
Sentiment:  negative
Materiality: 0.80
Item codes: 7.01, 9.01
LLM model:  deepseek-v4-flash:cloud@v2

AnaptysBio sues Tesaro and GSK for breach of collaboration agreement on dostarlimab
--------------------------------------------------------------------------------

- AnaptysBio filed suit in Delaware Chancery Court on Nov 20, 2025, alleging material breach of the Collaboration Agreement by Tesaro and GSK.
- Complaint seeks declaration that rights to dostarlimab revert to AnaptysBio within 60 days of notice of material breach.
- Allegations include Tesaro/GSK conducting clinical trials with competing PD-1 (Keytruda) instead of optimizing dostarlimab's commercial return, and failing to disclose trials.
- This follows a 2020 settlement where Tesaro/GSK paid $60M and doubled royalties; AnaptysBio claims violations continued post-settlement.
- Tesaro and GSK filed a counterclaim on Nov 26, 2025, claiming AnaptysBio breached the agreement.

Source:
  EDGAR index:    https://www.sec.gov/Archives/edgar/data/1370053/000137005325000103/0001370053-25-000103-index.htm
  Primary doc:    https://www.sec.gov/Archives/edgar/data/1370053/000137005325000103/anab-20251126.htm
  HTML page:      https://secwatch.observer/filing/0001370053-25-000103

License: Source filings: public domain (SEC EDGAR). Summaries (headline + bullets): CC-BY-4.0; attribute https://secwatch.observer