DeepSeek took the U.S. by storm this week: The Chinese company’s chatbot rose to the top of the Apple and Play stores, while major U.S. cloud providers like Microsoft began offering it on their platforms.

But “hundreds” of companies — especially ones with ties to government — have blocked the service, Bloomberg reported based on interviews with executives from cybersecurity firms Armis and Netskope.

“The biggest concern is the AI model’s potential data leakage to the Chinese government,” Armis’ CTO Nadir Izrael said. 

Bloomberg Law separately reported that a San Francisco law firm, Fox Rothschild, has blocked DeepSeek as well.

According to DeepSeek’s privacy policy, the company stores all user data in China, where local laws mandate companies share data with intelligence agencies upon request.

The Pentagon has just started blocking DeepSeek, while the Navy banned it last week.