TikTok, the immensely popular social media app whose China-based parent company has given rise to concerns about data security and foreign influence, is once again in Congress’s crosshairs.

The Republican-controlled House of Representatives overwhelmingly voted 352-65 to approve a bill requiring TikTok either be divested from ByteDance, its Beijing-based owner, or face a nationwide ban. The bill, called the Protecting Americans from Foreign Adversary Controlled Applications Act, now heads to the Senate.

It’s the latest front in a years-long battle to limit the app, which features short videos in a swipe-able Instagram-like interface. In 2020, President Donald Trump attempted to ban it through an executive order, but courts blocked his move after TikTok sued.

Here’s what to know about the bill.

WHAT’S BEHIND THE PUSH TO BAN TikTok?

Congressional Republicans have led some of the most aggressive proposals against TikTok, although some of those efforts have won the support of Democrats.

The bill’s primary backers, Rep. Mike Gallagher, R-Wis., and Raja Krishnamoorthi, D-Ill., say the app poses “a grave threat to U.S. national security” because of its Chinese ownership, and they warn that TikTok could be used to influence U.S. public opinion or harness user data to spy on Americans. ByteDance is controlled by Chinese authorities, they contend, and they describe the app as “Communist Party malware.”

“TikTok is a threat to our national security because it is owned by ByteDance, which does the bidding of the Chinese Communist Party,” Gallagher said Wednesday. “We know this because ByteDance leadership says so and because Chinese law requires it.”

The bill’s proponents, including powerful Democrats, have pushed back on the idea that they want an outright “ban” on TikTok, saying their objective is to rid it of foreign control. Rep. Nancy Pelosi, D-Calif., the former House speaker, said the bill is “an attempt to make TikTok better.”

Opponents of the measure say a ban would impinge on the freedom of expression of TikTok’s users. New York Rep. Alexandria Ocasio-Cortez, in a Wednesday social media post called the bill’s passage through the House “incredibly rushed” and said she would vote against the bill because of antitrust and privacy issues. Rep. Warren Davidson, R-Ohio, worried that the bill could open the door for banning other services, such as the Telegram social media app, or the stablecoin Tether.

Some senators previously have floated alternative proposals that would give federal authorities more power to counter foreign-controlled apps more broadly without targeting TikTok specifically. But the leaders of the Senate Intelligence Committee expressed support Wednesday for the legislation approved by the House.

Sens. Mark R. Warner, D-Va., and Marco Rubio, R-Fla., the chair and vice chair of the committee, said in a joint statement that they were “encouraged by today’s strong bipartisan vote in the House of Representatives, and look forward to working together to get this bill passed through the Senate and signed into law.”

TikTok spokesman Alex Haurek criticized the bill and the way it was passed.

“This process was secret and the bill was jammed through for one reason: It’s a ban,” Haurek said in a statement. “We are hopeful that the Senate will consider the facts, listen to their constituents, and realize the impact on the economy, 7 million small businesses, and the 170 million Americans who use our service.”

WHAT WOULD THE LEGISLATION DO?

The bill passed by the House requires that applications found to be controlled by a foreign adversary must be divested within 180 days, with ByteDance and TikTok specifically singled out.

Divestment could mean selling the app to a U.S.-based company, although the specific definition of a “qualified divestiture” would be determined by the U.S. president. The bill also creates a process for the president to designate certain social media apps as “subject to the control of a foreign adversary,” meaning other apps could be targeted as well.

If the bill becomes law and ByteDance refuses to sell, U.S.-based app stores and web-hosting services would be prohibited from providing TikTok to the public.

Congressional offices were flooded with calls Thursday after the company sent pop-up messages urging people to “speak up” against the bill. TikTok sent more notifications ahead of Wednesday’s vote.

Meanwhile, supporters of the bill said the pressure campaign highlights why the ban is needed.

“TikTok’s mass social manipulation tactics were on full display last week when foreign actors desperately used the app to push its 170 million American users to call members of Congress and pressure them to vote against this bill – leading to threats of suicide and violence from callers, providing exactly why this legislation is needed,” Ryan Walker, vice president of Heritage Action for America, said in a statement Monday.

WILL TikTok SHUT DOWN SOON?

No.

The bill still has to be approved by the Senate before it would go to President Biden who has said he would sign the measure. If it becomes law, ByteDance would have 180 days to find a buyer for TikTok before the ban takes effect, although a sale would probably be a complicated process.

The proposal also could be delayed or blocked in the courts. TikTok has used legal pressure to successfully oppose previous measures against it. A company spokesperson said in a Monday statement that the bill would strip 170 million Americans of their right to free expression, suggesting it might be challenged on constitutional grounds.

WHAT HAPPENS NEXT?

Although the bill quickly passed through the House by a wide margin, it faces a tougher path in the Democratic-led Senate. Top Democrats, including Warner and Maria Cantwell, D-Wash., have been pushing for their alternative proposals for months to address concerns that GOP-led efforts would explicitly and unconstitutionally target a specific company.

Although Warner and Rubio on Wednesday expressed support for the measure coming from the House, some Senate Republicans have been lukewarm on the bill. Sen. Rand Paul, R-Ky., said Tuesday that he might block any swift consideration, something he did last year on a similar piece of legislation. TikTok itself has lobbied furiously against the bill.

The two top 2024 presidential contenders, for their part, have also complicated the political dynamics. While Biden has thrown his support behind the House Republicans’ measure, Trump on Monday seemingly undercut his fellow Republicans by reversing his position and coming out against a potential TikTok ban.

In an interview on CNBC, Trump said he still thinks the app is a national security risk, but warned that a ban would lead to increased support for Facebook, which he lambasted as “an enemy of the people.”

“Frankly a lot of people are on TikTok that love it. Young kids on TikTok would go crazy without it. A lot of users,” Trump said.

Jacob Bogage, Drew Harwell and Will Oremus contributed to this report.