Mark Ruffalo Assumes 'Vindictive Motherf***ers' Larry & David Ellison Have Him 'On A List'

Mark Ruffalo doesn't think he'll be pulled in for many auditions if Paramount and Warner Bros. merge ... because, according to him, David and Larry Ellison aren't the "forgive and forget" types.

The actor talked about Paramount Skydance's controversial acquisition on a new episode of the "I've Had It" podcast ... joking that he's "already on a list" after his open letter opposing the merger gained thousands of signatures.

Ruffalo says the Ellisons spark a lot of fear in people ... quoting one person who told him "these are some vindictive motherf***ers, the Ellisons."

Two types of people are signing the open letter, Ruffalo says ... people like him -- big stars who have the privilege to oppose the merger -- and production people who simply can't afford not to.

As you know ... Paramount -- led by CEO David Ellison -- has thrown down $110 Billion to acquire WB after Netflix's $82.7 Billion offer was ultimately turned down. Many in the film industry have decried the move and have called on the government to deny the merger, citing antitrust laws.