U.S. lawmakers have written a letter to TikTok questioning its independence from its Chinese parent company ByteDance, in the wake of a recent report from The Wall St. Journal which noted that several high-level executives had been transferred from ByteDance to TikTok where they took on top roles across the organization. The report noted the former ByteDance execs now held key positions in advertising, HR, monetization, business marketing, and others related to TikTok’s e-commerce initiatives.

The letter, penned by senators Marsha Blackburn (R-TN) and Richard Blumenthal (D-CT), asks TikTok to explain why it’s hired several executives from ByteDance, “further calling into question the independence of TikTok’s operations and the security of its U.S. users’ information,” they wrote.

The WSJ’s report on the transfers suggested that the employee movement between the two organizations indicates that TikTok still maintains close ties to its Beijing-based parent, despite the video social network’s attempt to distance itself from its Chinese roots — and the applicable laws that could apply if the Chinese government were to pressure TikTok for its data or use the app in the spread of CCP propaganda.

TikTok, however, has consistently maintained its independence from China, even moving U.S. user data to Oracle servers in the U.S., in hopes of staving off a U.S.-wide TikTok ban.

Still, concerns about TikTok’s ties to China have led to the app being banned across a number of U.S. government-issued devices, including those in use by the U.S. House of Representatives and various U.S. states. Montana also became the first U.S. state to ban TikTok on personal devices, while New York City this summer became the latest government to ban TikTok from city-owned devices this summer, following a state-wide ban in 2020.

In the new letter, the senators noted that even TikTok employees had found the transfers “alarming” and reportedly joked that “TikTok is solving its ByteDance problem by moving ByteDance to the U.S.” It also stated that the relationship between the two entities “poses a unique risk to the security and privacy” of U.S. user data, and referenced earlier reports where TikTok had been found to be spying on U.S. journalists, for example.

TikTok, meanwhile, had promised U.S. officials there was a firewall between it and its parent company with the storage of U.S. user data on U.S. soil overseen by a U.S. company, the letter continued. But the transfers suggested that TikTok is “attempting to preserve ByteDance’s influence over TikTok while avoiding suspicion,” it read.

TikTok has been given until October 13 to respond to the various questions about the employee transfers the lawmakers posed. The full text of the letter can be read here, which includes questions about the employee transfers, the roles the employees now hold, and if any of the changes were disclosed to the Committee on Foreign Investment in the U.S. (CFIUS) prior to The WSJ’s reporting, among other things.

CFIUS’ review of TikTok began back in 2019 when the Trump administration was weighing a national ban. The agency holds the power to force TikTok to spin off its U.S. operations in lieu of ban if it didn’t believe the mitigation measures TikTok has enacted — like the move to Oracle servers — offered enough protection.