WASHINGTON, May 7 (Reuters) - TikTok and its Chinese

parent company ByteDance said on Tuesday they filed suit in U.S.

federal court seeking to block a law signed by President Joe

Biden that would force the divestiture of the short video app

used by 170 million Americans or ban its use.

The companies said they filed a lawsuit in the U.S. Court of

Appeals for the District of Columbia arguing that the law

violates the U.S. Constitution on a number of grounds, including

running afoul of First Amendment free speech protections. The

law, signed by Biden on April 24, gives China's ByteDance until

Jan. 19 to sell TikTok or face a ban.

TikTok made a copy of its lawsuit available to Reuters.

The lawsuit said the divestiture "is simply not possible:

not commercially, not technologically, not legally. ... There is

no question: the Act (law) will force a shutdown of TikTok by

January 19, 2025, silencing the 170 million Americans who use

the platform to communicate in ways that cannot be replicated

elsewhere."

Driven by worries among U.S. lawmakers that China could

access data on Americans or spy on them with the app, the

measure was passed overwhelmingly in Congress just weeks after

being introduced. The law prohibits app stores from offering

TikTok and bars internet hosting services from supporting TikTok

unless ByteDance divests TikTok by Jan. 19.

The suit also said the Chinese government "has made clear

that it would not permit a divestment of the recommendation

engine that is a key to the success of TikTok in the United

States."

It also said TikTok has spent $2 billion to implement

measures to protect the data of U.S. users and made additional

commitments in a 90-page draft National Security Agreement

developed through negotiations with the Committee on Foreign

Investment in the United States (CFIUS). That agreement included

TikTok agreeing to a "shut-down option" that would give the U.S.

government the authority to suspend TikTok in the United States

if it violated some obligations," according to the suit.

In August 2022, according to the lawsuit, CFIUS stopped

engaging in meaningful discussions about the agreement and in

March 2023 CFIUS "insisted that ByteDance would be required to

divest the U.S. TikTok business." CFIUS is an interagency

committee, chaired by the U.S. Treasury Department, that reviews

foreign investments in American businesses and real estate that

implicate national security concerns.

Biden could extend the Jan. 19 deadline by three months if

he determines ByteDance is making progress.

In 2020, then-President Donald Trump was blocked by the

courts in his bid to ban TikTok and Chinese-owned WeChat, a unit

of Tencent ( TCTZF ), in the United States. Trump, the

Republican candidate challenging Democratic President Joe Biden

in the Nov. 5 U.S. election, has since reversed course, saying

he does not support a ban but that security concerns need to be

addressed.

Many experts have questioned whether any potential buyer

possesses the financial resources to buy TikTok and if China and

U.S. government agencies would approve a sale.

To move the TikTok source code to the United States "would

take years for an entirely new set of engineers to gain

sufficient familiarity," according to the lawsuit.

The four-year battle over TikTok is a significant front in

the ongoing conflict over the internet and technology between

the United States and China. In April, Apple ( AAPL ) said China

had ordered it to remove Meta Platforms' ( META ) WhatsApp and

Threads from its App Store in China over Chinese national

security concerns.