Take-Two and its subsidiary Rockstar Games, which developed the hugely popular open-world action-adventure game, is now suing Pinkerton, arguing that the game’s characters are protected under the First Amendment and the fair use doctrine. “Put simply, Defendants cannot use trademark law to own the past and prevent creators from including historical references to Pinkerton agents in depictions of the American West,” Take-Two’s complaint says.

The publisher also notes in its complaint that dozens of other fictional works have referenced the historical Pinkerton Detective Agency (including the original Red Dead Redemption) and accuses the modern Pinkertons of trying to cash in on the success of Red Dead Redemption 2, which earned Rockstar $725 million in revenue over its first three days—the biggest opening weekend in the history of entertainment. (You can read the full complaint here.)

After the creation of the US Federal Bureau of Investigation in 1908, the Pinkertons started doing less for the US government, and more private protection work in the 20th century. Since being bought by Securitas in 1999, Pinkerton has been retained by telecommunications companies for labor disputes and Silicon Valley titans for corporate surveillance. Both Google and Facebook have hired Pinkerton, the Guardian reported last year.

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