Celsis In Vitro, Inc. v. CellzDirect, Inc.
United States Court of Appeals for the Federal Circuit
664 F.3d 922 (Fed. Cir. 2012)
Celsis (plaintiff) patented a method for multi-cryopreserving pooled liver cells (hepatocytes) from multiple donors, selling a product called LiverPool practicing the patent; competitor Life Technologies Corp. (LTC, defendant) sold a similar pooled multi-cryopreserved hepatocyte product, and Celsis sued for infringement, seeking a preliminary injunction, which the district court granted. LTC appealed, arguing it hadn't infringed because its process included a step the patent described as "not required," and that the patent was likely obvious given numerous journal articles discussing hepatocytes and cryopreservation generally (though none specifically addressed multi-cryopreservation).
Whether a district court abused its discretion in granting a preliminary injunction against an alleged patent infringer prior to a final ruling on liability, based on the patentee's likelihood of success, irreparable harm, the balance of hardships, and the public interest.