Cree shares soared above $23 a share on Thursday following news of a favorable court ruling in Taiwan and a stock rating upgrade.

Cree (Nasdaq: CREE) had fallen sharply in recent months due to a series of lawsuits filed by one of its co-founders and former CEOs, Eric Hunter. The stock had fallen below $14 but has been rallying since the company won favorable court rulings on Aug. 14.

ThinkEquity upgraded Cree to “overweight” from “equal rate” on Thursday. Cree stock traded as high as $23.64 before falling back to $21.04. It was up 8.7 percent or $1.68, for the day. Share volume of was five times higher than normal.

The court ruling came in Taiwan. Nichia Corp., a partner of Cree received a preliminary court injunction against a rival manufacturer of light-emitting diodes in a patent dispute. Nichia is battling Epistar Corp.