Over the past few months, lawmakers have taken aim at Big Tech, calling out companies like Facebook for anti-competitive behavior and sometimes threatening to break them up entirely. But on Tuesday, a bipartisan group of lawmakers is expected to introduce a new bill with the goal of encouraging market competition by requiring large platforms to make their users’ data interoperable.

The “Augmenting Compatibility and Competition by Enabling Service Switching” (ACCESS) Act would, in theory, force tech giants like Facebook and Google to make their services interoperable with those provided by smaller companies. In a press release announcing the bill, the senators claimed that by requiring data interoperability and portability for platforms, the legislation would encourage more competition in the social networking and messaging markets.

The bill would require platforms to maintain interfaces, similar to APIs, that would facilitate the “secure transfer of user data” to both a user or a competing service in a “commonly used, machine-readable format.”

As part of Europe’s General Data Protection Regulation, tech companies are already required to roll out new import and export tools for data, but the ACCESS Act is more involved, forcing these platforms to create new interfaces that their direct competitors have access to. The bill was spearheaded by tech hawk Sen. Mark Warner (D-VA) and a bipartisan pair of colleagues, Sens. Josh Hawley (R-MO) and Richard Blumenthal (D-CT).

“By making it easier for social media users to easily move their data or to continue to communicate with their friends after switching platforms, startups will be able to compete on equal terms with the biggest social media companies,” Warner said. “And empowering trusted custodial companies to step in on behalf of users to better manage their accounts across different platforms will help balance the playing field between consumers and companies.”

“Your data is your property. Period.”

Earlier this year, Facebook CEO Mark Zuckerberg announced what he called a new privacy-focused future for the company. In a blog post outlining his thinking, Zuckerberg focused heavily on the concept of data interoperability, saying, “People should be able to use any of our apps to reach their friends, and they should be able to communicate across networks easily and securely,” but he didn’t mention Facebook’s products and data working across platforms the company doesn’t already own. Facebook already has its own data download system, in accordance with GDPR requirements, but it can be unwieldy to use and likely would not fulfill the requirements of the ACCESS Act.

If approved, the ACCESS Act would allow users to sign up for a third-party data management service that would work as an intermediary for managing their privacy and account settings across platforms. This “third-party custodial service,” as the bill refers to it, would need to register with the Federal Trade Commission and adhere to any rules created by the agency governing them that are spurred from the passage of this bill. Notably, these services will likely not be free for users. The text of the bill explicitly says that these services could charge users a fee, but it doesn’t outline how much that could cost.

“Your data is your property. Period. Consumers should have the flexibility to choose new online platforms without artificial barriers to entry,” Hawley said. “This bill creates long-overdue requirements that will boost competition and give consumers the power to move their data from one service to another.”

If this bill were to become law, large platforms like Facebook and Google would have only 120 days to tell competing platforms how to access their new interoperability interfaces.

In the aftermath of Facebook’s Cambridge Analytica scandal, lawmakers have increasingly begun to put out their own data privacy and security measures. Last week, Sen. Ron Wyden (D-O) introduced his “Mind Your Own Business Act,” which would allow users to opt out of data tracking and targeted advertising. Wyden’s bill focuses more on options that companies could provide, whereas the ACCESS Act creates room for this new third-party service to help users manage their privacy settings. In the ACCESS Act, platforms could implement a fee for these services, but Wyden’s bill also creates an option for lower-income Americans to use funds from the Federal Communications Commission’s Lifeline program to subsidize those costs. By doing so, this would ensure that “privacy does not become a luxury good,” a press release for that bill said. The ACCESS Act does not include any programs to subsidize these costs.

“The exclusive dominance of Facebook and Google have crowded out the meaningful competition that is needed to protect online privacy and promote technological innovation,” Blumenthal said. “As we learned in the Microsoft antitrust case, interoperability and portability are powerful tools to restrain anti-competitive behaviors and promote innovative new companies.”