A new document published on Monday says that Meta's top people, like CEO Mark Zuckerberg and Instagram head Adam Mosseri, thought TikTok was doing better than Meta in areas where Meta used to be good.

The document from February 2022 has talks between some Meta leaders about Facebook and Instagram's plans and their place in the market. In one message, Zuckerberg said Facebook was a "competitor" that had "lost popularity and progress." He also said TikTok creates a "feeling of shared understanding" where friends see the same popular internet jokes.

Mosseri also agreed that Facebook is now a competitor, saying it's not the main way people find new things anymore. He thought YouTube might be the best place to find new things now, but he expected TikTok to become more popular than YouTube later, based on Meta's information.

Mosseri wrote that the best way for Facebook to be different is to be the main place people find things. But it's surprising that TikTok is all video and is much more successful than Facebook. He guessed that TikTok is making the market for social media on phones bigger and is also taking users from TV, long videos, and Netflix.

Mosseri was correct. Studies showed that people, especially young people, spent more time watching TikTok than YouTube in the U.S. in 2021 and 2023, and last year TikTok started allowing longer videos to compete with YouTube.

Just this week, Netflix added something new to its mobile app, similar to TikTok. It's a feed of short videos shown vertically, suggesting films and shows based on what each person likes.

In the trial, the U.S. government is trying to show that Meta broke competition laws by buying companies like Instagram and WhatsApp. They say Meta did this to have complete control of the social media market. A document like this could hurt their case because, inside Meta, managers were talking about how Facebook was losing to TikTok.

For example, Zuckerberg said that even though Facebook was still the biggest app for daily or weekly users, people were not spending the most time on it anymore.

He also said that TikTok helps people feel like they share the same experiences. He explained that if you and your friends like the same things, you will probably see the same things on your TikTok feed.

The CEO explained, "This makes it social because you can assume your friends have seen the content. You don't need to send it to them. It would be great if we could do this with different topics and content on Facebook."

Other executives also contributed their perspectives.

WhatsApp boss Will Cathcart said that when TikTok users comment on a video about a specific topic, the algorithm will show them and other people who commented the same videos more often over time.

Stan Chudnovsky, who was a leader at Meta then, said that Meta had started to compete in a market where many companies were reducing their growth.

He said that just adding a new feature like Stories is not enough now because people have many other apps to use. He listed popular social apps in the U.S. like TikTok, Twitter, and others.

John Hegeman, who was in charge of advertising, agreed that TikTok was ahead in things like short videos, search features, and tools for making content. But he thought Meta could catch up if creators also posted on Reels.

However, he wasn't sure how far behind Meta was with the technology for machine learning and making things. The document shows that Meta thinks Facebook is not the strongest company in the social media market.

Also, other documents have appeared during the trial showing that Meta is afraid of competition. Zuckerberg also said last month in court that TikTok's success was dangerous for Meta's business and made it grow more slowly.