Seagen Inc. v. Daiichi Sankyo Company, Ltd.

  1. December 02, 2025

    Fed. Circ. Erases $41.8M Verdict Over Seagen Cancer Drug IP

    The Federal Circuit in a precedential opinion Tuesday reversed a $41.8 million verdict against Daiichi Sankyo for infringing a Seagen breast cancer treatment patent, saying a lower court should have found that the patent didn't adequately describe the claimed invention or enable a skilled person to use it.

  2. October 06, 2025

    Fed. Circ. Examines $41.8M Seagen Cancer Drug Patent Case

    With a $41.8 million infringement verdict against Daiichi Sankyo at stake, a Federal Circuit panel Monday grappled with whether a Seagen breast cancer treatment patent adequately described the claimed invention and would enable a skilled person to use it.

  3. September 30, 2025

    4 Federal Circuit Clashes To Watch In October

    The Federal Circuit will hear arguments next week in cases where a nearly $42 million patent win for Seagen hangs in the balance due to a later post-grant review invalidity decision and where Regenxbio is seeking to undo the invalidation of its gene therapy patent for covering a natural product.