id Software boss Todd Hollenshead has confirmed that id Tech 5 will not be licensed out to any third-party developers or publishers.
Speaking to our sister site Eurogamer.net he said that the engine would now only be used for id Software and Bethesda titles in the future.
"It's going to be used within ZeniMax, so we're not going to license it to external parties," said Hollenshead.
"It's like, look, this is a competitive advantage and we want to keep it within games we publish - not necessarily exclusively to id or id titles, but if you're going to make a game with id Tech 5 then it needs to be published by Bethesda, which I think is a fair thing."
Hollenshead said that the company was never in the business of challenging middleware rivals such as Epic and its Unreal Engine even though when id Tech 5 was first unveiled at QuakeCon in 2007 the company said it would pursue licensing deals with potential partners. Since then, the developer has been acquired by Bethesda Softworks parent ZeniMax Media, bringing the technology in-house.
"I think that [Epic] made a strategic choice to focus on the middleware service stuff, and we never pretended to be focused on technology licensing.
"It was that we made the technology for our games, and the philosophy was that with the one team the technology was wasted if you're just using it on one game, so we wanted to be able to license it out to a small number of developers.
"Epic's made a good business out of that so kudos to them, but I wouldn't change the way we've done things."
id Tech 5 is currently behind the new IP Rage, due for release next year on PC, Xbox 360 and PlayStation 3.