Over time, some tech companies have grown to a massive size, posing antitrust concerns. Now, some of the country’s retail giants are asking the Federal Trade Commission (FTC) to open up an antitrust investigation into Amazon and Google.

In a letter dated June 30, the Retail Industry Leaders Association (RILA) — including companies like Best Buy, Target, and Walmart — wrote to the FTC. Within the letter, the companies focused on one unique aspect: the role that information and data plays.

“Our view is that modern antitrust enforcement needs to be driven by a greater recognition that control over information can drive anticompetitive effect just as much as market power and price control,” the RILA wrote.

The United States has struggled with managing its big tech companies for some time. Part of the struggle is that these companies have a global reach that people are still trying to understand. However, that’s not an excuse for regulatory practices to not exist —especially at home.

“As digital commerce and digital tools become increasingly interwoven within the retail industry fabric, leading retailers encourage federal regulators to remain vigilant in policing the abuse of ISPs of information bottlenecks in ways that either impose excessive fees on users, or seek to skew the flow of information in potentially self-serving ways,” the letter states.

When you’re shopping, big tech companies control a lot more of what you buy than you might think. Take Google, for example — most people will look for an item on Google’s search engine, which means you’re getting access to information that is already filtered and sorted by Google.

The letter noted that it should be “quite concerning” to know that Amazon and Google “control the majority of all Internet product search.”

In other words, that means they can very easily shape what price and product information is actually reaching customers.

Concerns over this information being distorted are legitimate. In March, the European Union issued Google a €1.5 billion ($1.7 billion) fine after the company was found to be blocking rival online search advertisers.

In addition, the letter touches on Amazon’s “anticompetitive uses of data.” According to the RILA, Amazon amasses third-party sales data and sells its own products. That’s something the organization says poses, “clear antitrust concerns because of the unique characteristics of such a platform.”

Both the FTC and Department of Justice are due to begin antitrust scrutiny towards big tech companies. According to reports, the FTC will take on Amazon and Facebook while the DOJ focuses on Apple and Google. So, the RILA’s letter has some good timing.

The organization isn’t calling on the end of online shopping, but for the government to step up its regulations.

“To be clear, digital technology platforms and online marketplaces can provide significant benefits to consumers and sellers alike…Concerns arise, however, when these platforms achieve a level of dominance that enables them to disregard those interests,” the RILA wrote.