Warner Bros. has responded to the legal challenge from Bethesda Softworks. Last week, Bethesda filed suit against Warner Bros., calling the recently released Westworld mobile game a "blatant ripoff" of its own game, Fallout Shelter. In a statement, Warner Bros. acknowledges the similarities but says it is an original game and uses no source code from Fallout Shelter, as Bethesda alleges.

"As one of the world's leading creators of intellectual property, including the ground-breaking television series Westworld, Warner Bros. has a deep respect for intellectual property rights," the company said in a statement to GamesIndustry.biz. "As such, the assertions by Bethesda Softworks that Warner's Westworld mobile game improperly used source code from Bethesda's Fallout Shelter are as surprising as they are unsubstantiated."

Westworld was developed by Behaviour Interactive, which also worked on the original release of Fallout Shelter. That serves as a large part of Bethesda's complaint, which claims that Behaviour took code from one game and carried it onto another project.

"Warner Bros. has been assured by the game developer, Behaviour Interactive, that Bethesda's allegations are untrue and that none of Bethesda's code was used in the Westworld game. Moreover, contrary to Bethesda's baseless accusation, Warner Bros. at no time 'induced' Behaviour to use the Fallout Shelter code in Westworld."

The visual similarities are apparent, as Westworld has you building an underground lair as you manage the park above-ground. Bethesda's allegations go a step further, accusing Behaviour of copying actual game code, along with "game design, art, animations, gameplay features, and other elements."

The Warner Bros. statement denies it ever explicitly asked Behaviour for to imitate Fallout Shelter, but it notably relies on assurances from Behaviour to deny that any code was copied. Westworld is now available on mobile, while Fallout Shelter has been ported to various platforms since 2015--most recently to Nintendo Switch and PS4.