The rise of “in-app purchases” has been a major boon for online game developers, letting them profit from impulse buys by customers who might otherwise keep their credit cards tucked away. But that success also sparked a patent challenge by a shell company called GameTek LLC, which claimed that some of the biggest game makers around should be held liable for infringing its technology.

After netting a raft of settlements, GameTek’s litigation campaign finally hit a brick wall on Friday. Handing a win to lawyers at Gibson, Dunn & Crutcher and Kilpatrick Townsend & Stockton, a federal judge in San Francisco tossed GameTek’s claims against Zynga Inc., Electronic Arts Inc., Funzio Inc. and Crowdstar International Limited, ruling that the concept of charging players for mid-game purchases isn’t patentable in the first place.