TikTok has sued President Donald Trump’s administration for banning transactions with parent company ByteDance. “The [Trump] administration ignored our extensive efforts to address its concerns, which we conducted fully and in good faith,” TikTok wrote in a press release. “We do not take suing the government lightly, however we feel we have no choice but to take action to protect our rights, and the rights of our community and employees.”

The lawsuit alleges that Trump’s order violates due process protections, exceeds the scope of sanctions rules, and offers no evidence for its claims that TikTok presents a national security threat. It also argues that Trump ignored TikTok’s cooperation with the Committee on Foreign Investment in the United States (CFIUS), which reviews mergers like ByteDance’s acquisition of the app Musical.ly, later rebranded as TikTok in the US.

“The executive order is not rooted in bona fide national security concerns,” the complaint reads, noting that “independent national security and information security experts have criticized the political nature of this executive order, and expressed doubt as to whether its stated national security objective is genuine.”

TikTok cites some complex and unusual legal concerns around the order. It notes that personal communications and “informational materials” — potentially including apps — are typically exempt from sanctions. And it argues that TikTok’s app code is “an expressive means of communication” covered by the First Amendment.

Microsoft had already expressed interest in buying TikTok and committed to discussions with ByteDance before the order, but Trump’s sanctions increased pressure to sell. As TikTok notes, he also suggested that any deal would have to make the Treasury Department “a lot of money.”

TikTok confirmed over the weekend that it would sue, citing a “lack of due process” in the ban. Trump sanctioned ByteDance on August 6th under national security emergency powers, escalating a conflict that had been brewing for months. The order came alongside a ban on WeChat, a chat app owned by Chinese giant Tencent. A group of WeChat users have also sued the Trump administration over that order.

The White House hasn’t fully detailed what its ban would entail. It currently bans all transactions with ByteDance, but it doesn’t specify what a “transaction” entails. The rule was initially supposed to take effect in mid-September, but Trump later extended it, giving ByteDance until November 12th to sell TikTok.

Update 1:00PM ET: Added more details from lawsuit text.