Ricky Gervais–who created the original U.K. version of “The Office” but apparently doesn’t think NBC’s U.S. version is quite up to its standards–had plenty to say, most of it bad, about last night’s season finale, Entertainment Weekly reported.

Gervais did a cameo on the episode, appearing as part of a widely hyped celebrity lineup that included Jim Carrey, Ray Romano, Will Arnett, James Spader and even billionaire Warren Buffett. But Gervais apparently wanted to make it clear that he wasn’t endorsing the show. The actor wrote on his blog: “I assume most people know I didn’t do the US remake for the art. I did my version for the art. That’s why I stopped it after a few hours of telly.” The U.K. version ran for only 14 episodes.

In his blog, Gervais “expresses something like exasperation with the American version,” EW reported. “Noting that the season finale reminded him of the Chris Martin episode of ‘Extras’ (in which a celebrity cameo is awkwardly wedged into a sitcom), Gervais laughs, ‘If you’re going to jump a shark, jump a big one!’”

Gervais also swatted down rumors that he might be on tap to take over the boss’s office left vacant by Steve Carell. “You don’t start a company to work on reception,” he wrote.