SIONYX LLC v. HAMAMATSU PHOTONICS K.K., Appeal Nos. 2019-2359, 2020-1217 (Fed. Cir. December 7, 2020).  Before Lourie, Reyna, and Wallach.  Appealed from D. Mass. (Judge Saylor IV).   (Patent Ownership)


In 1998, a professor at Harvard invented a way to make “black silicon” by irradiating silicon with a laser.  He subsequently developed applications for black silicon with a student researcher named James Carey.  They later founded SiOnyx to commercialize black silicon.

SiOnyx and Hamamatsu entered a business partnership in 2007, in which SiOnyx shared its black silicon know-how with Hamamatsu, subject to a Non-Disclosure Agreement (NDA).  The purpose of this partnership was to jointly develop commercial products such as photodetectors using black silicon.  In 2008, Hamamatsu ended its relationship with SiOnyx, but continued to make products incorporating black silicon technology.  Hamamatsu filed several Japanese and U.S. patents covering these products.

SiOnyx began selling its own black silicon products in 2013.  In 2014, SiOnyx became aware of Hamamatsu’s patents, and the two parties met to discuss ownership of the patents.  When these meetings failed to produce an agreement, SiOnyx sued Hamamatsu for breach of the NDA and to add Carey as an inventor of Hamamatsu’s patents.

The district court ruled that Carey was a co-inventor of Hamamatsu’s patents, and that under the NDA, SiOnyx owned Hamamatsu’s U.S. patents because they arose from SiOnyx’s confidential information.  The district court did not award SiOnyx ownership of Hamamatsu’s Japanese patents, because it did not believe it had authority to do so.  Hamamatsu appealed for
ownership of its U.S. patents, and SiOnyx cross-appealed for ownership of Hamamatsu’s Japanese patents.


Did the district court err in awarding SiOnyx ownership of Hamamatsu’s U.S. patents, and not awarding SiOnyx ownership of Hamamatsu’s Japanese patents?  (continue reading)

Summary by:  Brian Repper

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