Thirteen privacy-focused tech companies including DuckDuckGo, Mozilla, and Proton wrote a letter to Congressional leaders voicing their support for a bill banning the self-preferencing seen on major tech platforms like Amazon.com (AMZN  ), Meta's Facebook (META  ), and Alphabet's Google (GOOGL  ). According to the letter writers, these tech giants unfairly steer customers towards their own products and away from products with tighter user-privacy protections.

"While more and more Americans are embracing privacy-first technologies, some dominant firms still use their gatekeeper power to limit competition and restrict user choice," the companies wrote in the letter, sent on September 13.

The antitrust bill seeks to stop tech giants from harming competition by unfairly preferencing their own products. This includes restricting platforms like Amazon and Google from giving preferential ranking to their own products and apps over other competitors on the store.

"Smaller, independent companies want to offer products that give people real control online," Mozilla's head of U.S. public policy and government affairs, Jennifer Hodges, said. "Due to harmful self-preferencing practices, a small number of giants dictate what we experience online."

The bill is co-sponsored by Senators Amy Klobuchar, Democrat, and Chuck Grassley, Republican. Klobuchar, known for her support of antitrust regulation, has been pushing hard to get the bill passed, and she says she now has the votes she needs to get it passed.

"We must pass legislation to put rules of the road in place for dominant tech companies," Klobuchar said in a statement in July. "These platforms use their dominance to unfairly disadvantage their rivals, all at the expense of competition and consumers."

Still, according to Reuters, it's unlikely that the bill will become law before the end of 2022. With midterm elections around the corner, lawmakers' attention is shifting away from issues like antitrust and towards more hot-button topics, something that Apple (AAPL  ) seemed to reference in a letter to the Senate Judiciary Committee in January.

"After a tumultuous year that witnessed multiple controversies regarding social media, whistleblower allegations of long-ignored risks to children and ransomware attacks that hobbled critical infrastructure, it would be ironic if Congress responds by making it much harder to protect the privacy and security of Americans' personal devices," Apple wrote.

Apple is directly challenging the smaller companies' claims that its self-preferential behavior directs users away from products with more robust privacy controls. In fact, the tech giants argue that the bill would make it harder, not easier, for customers to find the most useful products.

"Americans might get worse, less relevant and less helpful versions of products," Google wrote in a January blog. "While these bills might help the companies campaigning for them, including some of our major competitors, that would come at a cost to consumers and small businesses."