Simpson Thacher Secures Complete Dismissal of Putative Shareholder Class Action Against Vivo Capital
On May 18, 2026, the Delaware Court of Chancery dismissed a putative class action concerning Sinovac Biotech Ltd. (“Sinovac”), an Antigua-incorporated and China-based biopharmaceutical company. Plaintiffs brought claims alleging shareholder oppression, wrongful dilution, and breach of fiduciary duty against Sinovac and certain of its directors, as well as claims for aiding and abetting and unjust enrichment against Vivo Capital LLC and its affiliated entities (together, the “Vivo Defendants”). The Court dismissed the claims on the basis of forum non conveniens.
Simpson Thacher & Bartlett LLP represented the Vivo Defendants and their designee on Sinovac’s Board of Directors.
The Simpson Thacher team was led by Stephen P. Blake, with Wendy Shidi Wu and Won Ki Lee.