Instagram head Adam Mosseri takes witness stand in Meta antitrust trial: Recalls the email he had to send from paternity leave

Instagram chief Adam Mosseri testified Thursday in Meta's high-stakes antitrust trial, revealing tensions between Facebook's leadership and Instagram's founders that ultimately led to their departure in 2018.During more than six hours of testimony, Mosseri disclosed that while on paternity leave, he warned CEO Mark Zuckerberg about deteriorating relations with Instagram cofounders Kevin Systrom and Mike Krieger."It was hard for me to get a read on what's going on as the relationship was strained," Mosseri wrote in the 2018 email, acting as mediator between the increasingly frustrated founders and Facebook leadership.The conflict centered on Zuckerberg's strategy decisions, which Instagram's founders believed were deliberately constraining their platform's growth to benefit Facebook's core business.Mosseri characterized TikTok as "probably the fiercest competition we have faced during my tenure at the company," admitting that Instagram's initial response to the Chinese-owned platform was inadequate."We could have and should have been more aggressive," Mosseri testified, calling Instagram's first version of Reels his "biggest mistake" built on "not a sound foundation."Internal documents revealed Instagram estimated that TikTok caused a 40% year-over-year decline in time spent on their platform.Mosseri also acknowledged massive spending on content creators, testifying that Meta has invested "hundreds of millions, maybe a billion or two" to support creators while competing for talent with rivals.The FTC lawsuit claims Meta violated antitrust laws by cementing an illegal monopoly through its acquisitions of Instagram in 2012 and WhatsApp in 2014. If successful, the case could force Meta to divest both platforms in what would be one of the most consequential antitrust rulings in decades.Judge James Boasberg will ultimately decide the case, which features testimony from more than two dozen witnesses, including Mark Zuckerberg