A dozen advocacy groups are launching a new campaign on Friday to block Tesla CEO Elon Musk’s $44 billion purchase of Twitter, warning that he will downgrade important safeguards on the platform if it fails. he is allowed to take control.

The Stop the Deal campaign, shared exclusively with CNBC, includes plans to pressure government agencies to review the acquisition, persuade Tesla shareholders to take action against it, and ask advertisers to withdraw spending from the platform.

This highlights concerns that many progressives have shared about how Musk’s acquisition and plans for a more open platform could allow for more widespread hate and harassment on the platform.

Participating nonprofits include Accountable Tech, Center for Countering Digital Hate, GLAAD, and MediaJustice.

Musk has reportedly already undergone regulatory review over the deal, which he recently said was “on hold,” as he seeks more information about the number of fake accounts on the platform. Twitter executives reportedly told employees that was not the case. In the time since the deal and that tweet, Twitter’s shares have fallen amid the broader recession, leading some analysts to speculate it may be looking for a better price.

The groups behind the Stop the Deal campaign warn on their website that Musk would “crush basic content moderation safeguards and provide a bullhorn to extremists who traffic white nationalism, hate, misinformation and harassment – ​​further endangering marginalized communities”. The campaign site predicted that Musk would “reinstate the Twitter accounts of public figures who had been banned for inciting violence and spreading dangerous misinformation.”

While he doesn’t mention former President Donald Trump by name, it could apply to him, as he was suspended from the platform following the Jan. 6 uprising at the U.S. Capitol.

Musk said his motivation behind buying Twitter was driven by his penchant for service and his belief that it should serve as a more open forum for a variety of ideas. Musk envisioned a platform with fewer rules about what speech is and isn’t allowed, though he acknowledged he would still have to follow international laws. He also said permanent bans, such as the one currently active against Trump, should generally be favored over temporary bans.

But Stop the Deal organizers say less content moderation doesn’t necessarily mean freer speech and say it will lead to more harassment of marginalized communities.

“Elon Musk’s takeover of Twitter will not lead to more ‘free speech’ on the platform,” Rahna Epting, executive director of MoveOn, said in a statement. “It will just lead to more extreme voices exploiting the platform to stoke hate, violence and harassment. Social media platforms that are nothing more than toxic cesspools of misinformation are harmful to our society and to our policy.”

“With more and more threats of online violence manifesting offline, platforms are finally listening to our demands for accountability in creating a safer online space for everyone, but especially black and brown women. and LGBTQ+ people,” Bridget Todd, director of communications for UltraViolet, said in a statement.

Stop the Deal organizers urged users to tweet their opposition to Musk, Twitter advertisers and Tesla shareholders.

In the legal and regulatory arena, the groups say the government could take several steps to block the deal. One option would be for the Securities and Exchange Commission to ban Musk from being a director or officer of a public company, citing among other actions his failure to properly disclose his initial investment in Twitter.

The coalition says the Committee on Foreign Investment in the United States could also adjust the terms of the agreement if it determines that foreign investment threatens national security. They pointed to a disclosure that said the deal would be funded in part by Saudi Prince Alwaleed bin Talal Al Saud and Qatar’s sovereign wealth fund.

The group also said the Federal Trade Commission could take legal action to block the deal if it is determined to lessen competition. But that route would likely be complicated by Twitter’s relatively small share of the social media market compared to peers such as Meta’s Facebook.

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WATCH: A timeline of the Elon Musk-Twitter takeover saga