Over 65 tech companies, open Internet advocates and other organizations released two open letters to negotiators of the secretive Trans-Pacific Partnership (TPP) on Wednesday, expressing their concern that the trade deal’s approval will force websites to censor content and block Internet users.

Spearheaded by the United States, the TPP––dubbed a “free trade” deal––includes twelve of the world’s most economically-prosperous countries that cumulatively account for 40 percent of the global economy. With the possibility of wide-reaching effects on everything from Internet freedom to the prices of medicine in developing countries, critics have slammed it as a “corporate coup d’etat” and “NAFTA on steroids.” Although the text of the deal has not been seen in its entirety by anyone outside of the negotiations, a draft version of the intellectual property rights section of the deal was released last November by WikiLeaks, and Internet rights groups have voiced their opposition ever since.

The two letters have been signed by a wide range of organizations, including the Electronic Frontier Foundation (EFF), Creative Commons and Reddit.

In a statement on the letters, the EFF declared that “with no official means of participating in the negotiations, the global community of users and innovators who will be affected by these proposed changes have been limited to expressing their concerns through open letters to their political representatives and to the officials negotiating the agreement.”

According to the same statement, the so-called intermediary liability proposals contained in the draft released by WikiLeaks would require websites “to adopt a facsimile of the DMCA to regulate the take-down of material hosted online, upon the mere allegation of copyright infringement by a claimed rights-holder.”