X has initiated a federal antitrust lawsuit against the Global Alliance for Responsible Media (GARM) and several major advertisers, including Unilever and Mars, alleging a conspiracy to withhold advertising funds following Elon Musk's acquisition of the platform.

The lawsuit claims that GARM encouraged a boycott of X, leading to significant revenue losses for the platform, which has seen ad revenues decline by approximately half since Musk took over.

X CEO Linda Yaccarino stated that the alleged coordinated boycott threatens the company's future and undermines free expression on the platform.

The decline in advertising revenue has been attributed to concerns from brands about their ads appearing next to harmful content, particularly amid rising antisemitic posts and reduced content moderation.

The lawsuit details that the involved companies agreed to uniformly reduce their advertising expenditures on X, which X argues may violate antitrust laws.

In response to the allegations, a GARM spokesperson emphasized that participation in the initiative is voluntary and that companies retain the freedom to choose their advertising strategies.

Legal experts suggest that the lawsuit may face challenges, as politically motivated boycotts are generally protected under the First Amendment.

Musk has publicly declared that the lawsuit marks a significant shift in strategy, stating, 'now it is war' against advertisers who withdraw from the platform.

Yaccarino aims to leverage the lawsuit announcement to attract new advertisers by arguing that the revenue decline is directly linked to the boycott.

This lawsuit is not X's first related to its declining ad business; it previously sued the Center for Countering Digital Hate, which was dismissed by a federal judge.

The lawsuit focuses on events from the early days of Musk's ownership, rather than a subsequent dispute that arose a year later.

The case has been assigned to US District Judge Reed O'Connor in Texas, known for handling conservative lawsuits.