Elon Musk’s X Corp., the parent company of the platform formerly known as Twitter, on Friday sued California’s attorney general over the state’s new content moderation law.

California Gov. Gavin Newsom signed bill AB 587 into law last September. The law requires social media companies to post their terms of service online and submit a semiannual report to the state attorney general outlining their content moderation policies and practices. Platforms must, among other things, disclose how their automated content moderation systems work, how they define controversial content categories such as “hate speech” and “disinformation,” and the number of pieces of content flagged or removed in such categories.

Newsom’s office touted the bill as a way to improve transparency from social networks. But in a complaint filed in California’s Eastern District Court against California Attorney General Robert Bonta, X alleged that the law violates the First Amendment and California’s constitution by potentially compelling the company to moderate users’ politically charged speech.

The law “compels companies like X Corp. to engage in speech against their will, impermissibly interferes with the constitutionally-protected editorial judgments of companies such as X Corp., has both the purpose and likely effect of pressuring companies such as X Corp. to remove, demonetize, or deprioritize constitutionally-protected speech,” the company alleged in the complaint. It added that the law could place an “undue burden” on social media companies such as Musk’s X, which is headquartered in California.

Attorney General Bonta’s press office said in an email to CNN: “While we have not yet been served with the complaint, we will review it and respond in court.”

A spokesperson for Newsom sent CNN a statement from last September in which the governor remarked on the bill.

“California will not stand by as social media is weaponized to spread hate and disinformation that threaten our communities and foundational values as a country,” Newsom said in the statement. “Californians deserve to know how these platforms are impacting our public discourse, and this action brings much-needed transparency and accountability to the policies that shape the social media content we consume every day.”

The lawsuit comes as Musk has escalated his rhetoric over what kinds of speech should be permitted on his platform, as the company’s core advertising business has taken a major revenue hit over concerns, among other things, about the approach to content moderation. Under Musk’s leadership, the platform has made several changes to its content policies, including ceasing enforcement of its Covid-19 misinformation policy and reinstating many previously banned users.