U.S. District Court Judge Donald Malloy is shutting the door on Montana's attempt to block the use of TikTok, saying the measure by the Legislature last spring is "unconstitutional".

Montana had become the first state in the country to block TikTok over concerns that the Chinese-based app was stealing American data and presenting a security risk. Governor Gianforte signed the bill into law after the session.

But in the 48-page ruling finally released Thursday afternoon, Judge Donald Malloy faulted the state for overstepping its authority. He wrote that the attempted prohibition "oversteps state powers and infringes on Constitutional rights" of both the companies and the app users.

While Malloy's analysis did defend the state's ability to protect residents from "harm", he questioned the outright ban.

"In shutting off TikTok, the Legislature has both harmed User Plaintiffs’ First Amendment rights and cut off a stream of income on which many rely," Malloy wrote. "Thus, Plaintiffs have established a likelihood of irreparable harm. Notably, neither party takes issue with the Governor’s mandate that TikTok is banned from all state computers."

"Although TikTok’s business harms argument is not entirely persuasive, the State has not substantively rebutted it."

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Trial for final arguments

Malloy noted that "while the state argues the law's local benefits are significant, and they may be," he said the state hadn't provided "any evidentiary support" to back those arguments.

The ban would have gone into effect at the first of the year and imposed fines on companies that allowed it to be downloaded. Now, the preliminary injunction blocks the ban, but the dispute is still scheduled to be reviewed in a trial next year.

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