Two of the main members of the PayPal mafia are sparring again — this time over artificial intelligence.

Billionaire tech investor and LinkedIn co-founder Reid Hoffman on Monday called Anthropic “one of the good guys” after the AI startup was criticized last week by David Sacks, the venture capitalist serving as President Donald Trump’s AI and crypto czar.

“Anthropic, along with some others (incl Microsoft, Google, and OpenAI) are trying to deploy AI the right way, thoughtfully, safely, and enormously beneficial for society,” Hoffman wrote on X. “That’s why I am intensely rooting for their success.”

Hoffman has served on Microsoft’s board since 2017, shortly after selling LinkedIn to the software giant. Microsoft is a key OpenAI investor and partner. Hoffman was also an early investor in OpenAI, Anthropic’s larger rival, and remains a shareholder. He revealed on Monday that Greylock, where he’s a partner, has invested in Anthropic.

Greylock and Anthropic didn’t respond to requests for comment.

In a series of posts, Hoffman said he tries to avoid commenting directly about companies like OpenAI and Anthropic, but that “in all industries, especially in AI, it’s important to back the good guys.”

Hoffman and Sacks were both early employees at PayPal, joining in 1999 and assuming major roles at the payments company. Along with Peter Thiel, Elon Musk, Max Levchin and a group of other high-profile techies, they were part of what became known as the PayPal mafia because of the number of successful companies they went on to build.

But Hoffman and Sacks have been public antagonists recently, due mostly to their political differences. Hoffman is a major Democratic donor, contributing millions of dollars to Kamala Harris’ unsuccessful presidential bid.

Sacks emerged as a vocal Trump supporter ahead of the 2024 election before joining the administration. He hosted a fundraiser for Trump at his San Francisco mansion.

Anthropic was founded in 2021 by a group of former OpenAI executives and researchers who left the company over concerns about safety. Jack Clark, one of the startup’s co-founders and its current head of policy, added fuel to the debate about regulation last week, publishing an essay called “Technological Optimism and Appropriate Fear.”

Sacks criticized the essay and, in a post on X, accused Anthropic of “running a sophisticated regulatory capture strategy based on fear-mongering.” He said the company is “principally responsible for the state regulatory frenzy that is damaging the startup ecosystem.”

Anthropic has repeatedly pushed back against efforts by the federal government to hinder state-level regulation of AI, including a Trump-backed provision that would have blocked those rules for 10 years.

After Hoffman shared his thoughts about Anthropic on Monday, Sacks and Musk, who owns a competing AI company called xAI and was also a major early figure in the second Trump administration, were quick to respond.

“The leading funder of lawfare and dirty tricks against President Trump wants you to know that ‘Anthropic is one of the good guys,'” Sacks wrote in response to Hoffman on Monday. “Thanks for clarifying that. All we needed to know.”

“Indeed,” Musk said in a reply.

The chirping went back and forth on Monday.

“Shows you didn’t read the post (not shocked),” Hoffman wrote. “When you are ready to have a professional conversation about AI’s impact on America, I’m here to chat.”

Jason Calacanis, who co-hosts the All-In podcast, along with Sacks and two other tech friends, wrote in response to Hoffman that he should “come on the pod,” inviting him this week. Hoffman previously joined for an episode at the end of August, roughly two months before the presidential election.

Hoffman wrote that he is “open to coming back on” but that “this week is packed.”

— CNBC’s MacKenzie Sigalos contributed to this report

WATCH: Anthropic’s Mike Krieger on new model release and the race to build real-world AI agents

OpenAI announced on Monday in a joint statement that it will be working with Bryan Cranston, SAG-AFTRA, and other actor unions to protect against deepfakes on its artificial intelligence video creation app Sora.

The “Breaking Bad” and “Malcolm in the Middle” actor expressed concern after unauthorized AI-generated clips using his voice and likeness appeared on the app following the Sora 2 launch at the end of September, the Screen Actors Guild-American Federation of Television and Radio Artists said in a post on X.

“I am grateful to OpenAI for its policy and for improving its guardrails, and hope that they and all of the companies involved in this work, respect our personal and professional right to manage replication of our voice and likeness,” Cranston said in a statement.

Along with SAG-AFTRA, OpenAI said it will collaborate with United Talent Agency, which represents Cranston, the Association of Talent Agents and Creative Artists Agency to strengthen guardrails around unapproved AI generations.

The CAA and UTA previously slammed OpenAI for its usage of copyrighted materials, calling Sora a risk to their clients and intellectual property.

OpenAI had to block videos of Martin Luther King Jr. on Sora last week at the request of King’s estate after users created “disrespectful depictions” of the civil rights leader.

Zelda Williams, the daughter for late comedian Robin Williams, asked people to stop sending her AI-generated videos of her father shortly after the Sora 2 release.

OpenAI’s approach to copyright restrictions and other issues related to likeness have evolved since the Sora 2 launch Sept. 30.

On Oct. 3, CEO Sam Altman updated Sora’s opt-out policy, which previously allowed the use of IP unless studios specifically requested that their material not be used, to allow rightsholders “more granular control over generation of characters.”

At launch, Sora required an opt-in for the use of an individual’s voice and likeness, though OpenAI said that it is now also committing to “responding expeditiously to any complaints it may receive.”

The company reiterated its support of the NO FAKES Act, a federal bill passed designed to protect against unauthorized AI-generated replicas of people’s voice or visual likeness.

“OpenAI is deeply committed to protecting performers from the misappropriation of their voice and likeness,” Altman said in a statement. “We were an early supporter of the NO FAKES Act when it was introduced last year, and will always stand behind the rights of performers.”