The Supreme Court agreed to hear a dispute between Teva Pharmaceuticals and Helsinn Healthcare over patents for Helsinn’s anti-nausea drug Aloxi (palonosetron hydrochloride).

At issue is whether an inventor’s sale of an invention to a third party that is obligated to keep it confidential qualifies as prior art for patent purposes. A federal appeals court previously ruled against the idea of safe harbor for sales that do not disclose the details of the claimed invention.

The appeals court sided with Teva, invalidating patents relating to Aloxi. The court cited the 2011 America Invents Act’s “on-sale bar” to patentability.

Teva launched a generic version of Aloxi in the United States in March.