Denying WhatsApp co-founder Brian Acton’s claims that Facebook CEO Mark Zuckerberg tried to undermine the instant messaging app’s encryption technology, a top Facebook executive called Acton “low-class”.

Acton started WhatsApp with Jan Koum. Facebook acquired the messaging service about four years ago for $22 billion. Acton quit Facebook a year ago, and Koum too left the company in April.

In an interview with Forbes, published on Wednesday, Acton alleged that Zuckerberg was in a rush to make money from the messaging service and undermine elements of its encryption technology, CNBC reported.

WhatsApp co-founders Brian Acton (left) and Jan Koum (Image: Forbes)
WhatsApp co-founders Brian Acton (left) and Jan Koum (Image: Forbes)

Slamming Acton for his allegations, Facebook’s David Marcus, who ran Facebook’s messaging products before starting the blockchain group earlier this year, said that the global roll-out of end-to-end encryption on WhatsApp happened after the acquisition, and with Zuckerberg’s full support.

Yes, Jan Koum played a key role in convincing Mark of the importance of encryption, but from that point on, it was never questioned,” Marcus wrote in a Facebook post, expressing his “personal views”.

Mark’s view was that WhatsApp was a private messaging app, and encryption helped ensure that people’s messages were truly private,” he added.

Speaking on the business model, Marcus said that Zuckerberg protected WhatsApp for a very long period of time.

Acton, according to Marcus, actively slow-played the execution of a paid messaging service.

… while advocating for business messaging, and being given the opportunity to build and deliver on that promise, Brian actively slow-played the execution, and never truly went for it,” Marcus wrote.

Lastly — call me old fashioned. But I find attacking the people and company that made you a billionaire, and went to an unprecedented extent to shield and accommodate you for years, low-class,” he said.

It’s actually a whole new standard of low-class.

Facebook got another jolt this week when Instagram founders Mike Krieger and Kevin Systrom quit the company late on Monday.

Founded in 2010, Instagram was bought by Facebook for $1 billion in 2012.