• Elon Musk's X implemented new terms of service that are driving some users off the microblogging platform. 
• The new terms include expansive permissions requiring users to allow the company to use their data to train X's artificial intelligence models.
• The terms also say users could be liable for $15,000 in damages if they use the platform too much. 

X's new terms of service, which took effect Nov. 15, are driving some users off Elon Musk's microblogging platform. 

The new terms include expansive permissions requiring users to allow the company to use their data to train X's artificial intelligence models while also making users liable for as much as $15,000 in damages if they use the platform too much. 

The terms are prompting some longtime users of the service, both celebrities and everyday people, to post that they are taking their content to other platforms. 

"With the recent and upcoming changes to the terms of service — and the return of volatile figures — I find myself at a crossroads, facing a direction I can no longer fully support," actress Gabrielle Union posted on X the same day the new terms took effect, while announcing she would be leaving the platform.

"I'm going to start winding down my Twitter account," a user with the handle @mplsFietser said in a post. "The changes to the terms of service are the final nail in the coffin for me."

It's unclear just how many users have left X due specifically to the company's new terms of service, but since the start of November, many social media users have flocked to Bluesky, a microblogging startup whose origins stem from Twitter, the former name for X. Some users with new Bluesky accounts have posted that they moved to the service due to Musk and his support for President-elect Donald Trump.

Bluesky's U.S. mobile app downloads have skyrocketed 651% since the start of November, according to estimates from Sensor Tower. In the same period, X and Meta's Threads are up 20% and 42%, respectively. 

X and Threads have much larger monthly user bases. Although Musk said in May that X has 600 million monthly users, market intelligence firm Sensor Tower estimates X had 318 million monthly users as of October. That same month, Meta said Threads had nearly 275 million monthly users. Bluesky told CNBC on Thursday it had reached 21 million total users this week.

Here are some of the noteworthy changes in X's new service terms and how they compare with those of rivals Bluesky and Threads.

Artificial intelligence training

X has come under heightened scrutiny because of its new terms, which say that any content on the service can be used royalty-free to train the company's artificial intelligence large language models, including its Grok chatbot.

"You agree that this license includes the right for us to (i) provide, promote, and improve the Services, including, for example, for use with and training of our machine learning and artificial intelligence models, whether generative or another type," X's terms say.

Additionally, any "user interactions, inputs and results" shared with Grok can be used for what it calls "training and fine-tuning purposes," according to the Grok section of the X app and website. This specific function, though, can be turned off manually. 

X's terms do not specify whether users' private messages can be used to train its AI models, and the company did not respond to a request for comment.

"You should only provide Content that you are comfortable sharing with others," read a portion of X's terms of service agreement.

Though X's new terms may be expansive, Meta's policies aren't that different. 

The maker of Threads uses "information shared on Meta's Products and services" to get its training data, according to the company's Privacy Center. This includes "posts or photos and their captions." There is also no direct way for users outside of the European Union to opt out of Meta's AI training. Meta keeps training data "for as long as we need it on a case-by-case basis to ensure an AI model is operating appropriately, safely and efficiently," according to its Privacy Center. 

Under Meta's policy, private messages with friends or family aren't used to train AI unless one of the users in a chat chooses to share it with the models, which can include Meta AI and AI Studio.

Bluesky, which has seen a user growth surge since Election Day, doesn't do any generative AI training. 

"We do not use any of your content to train generative AI, and have no intention of doing so," Bluesky said in a post on its platform Friday, confirming the same to CNBC as well.

Liquidated damages

Another unusual aspect of X's new terms is its "liquidated damages" clause. The terms state that if users request, view or access more than 1 million posts – including replies, videos, images and others – in any 24-hour period they are liable for damages of $15,000.

While most individual users won't easily approach that threshold, the clause is concerning for some, including digital researchers. They rely on the analysis of larger numbers of public posts from services like X to do their work. 

X's new terms of service are a "disturbing move that the company should reverse," said Alex Abdo, litigation director for the Knight First Amendment Institute at Columbia University, in an October statement. 

"The public relies on journalists and researchers to understand whether and how the platforms are shaping public discourse, affecting our elections, and warping our relationships," Abdo wrote. "One effect of X Corp.'s new terms of service will be to stifle that research when we need it most."

Neither Threads nor Bluesky have anything similar to X's liquidated damages clause. 

Meta and X did not respond to requests for comment.

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