The Federal Trade Commission (FTC) alleged in a Thursday court filing that Amazon executives, including founder Jeff Bezos and CEO Andy Jassy, discussed “sensitive business matters” in now-erased text messages that could have been used as evidence in the FTC’s ongoing antitrust case against Amazon.

According to the Thursday filing, senior Amazon leaders used the encrypted Signal messaging app from April 2019 to May 2022 and continued to delete messages through the app’s disappearing message feature — even when the FTC was investigating Amazon.

“Amazon executives deleted many Signal messages during Plaintiffs’ pre-Complaint investigation, and Amazon did not instruct employees to preserve Signal messages until over fifteen months after Amazon knew that Plaintiffs’ investigation was underway,” the FTC wrote in the filing.

^{Amazon founder Jeff Bezos. Photo by SAUL LOEB/AFP via Getty Images}

The FTC named Bezos, as well as other senior executives like Amazon’s top lawyer David Zapolsky, as some of the leaders that used Signal and its disappearing messages feature.

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The filing is one piece of a bigger antitrust case that kicked off in September when the FTC sued Amazon, accusing the retail giant of illegally maintaining a monopoly through anticompetitive practices.

Amazon responded that the lawsuit could negatively impact both the consumers who shop on its platform with higher prices and the independent businesses that sell products through it.

In Thursday’s filing, the FTC asked for more information about how Amazon’s leadership told employees to communicate on Signal, including when to use it and if there were specific instructions about deleting messages.

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Amazon spokesperson Tim Doyle told Bloomberg that the FTC’s allegations were “baseless” and that Amazon disclosed its Signal use to the FTC “years ago.”

Doyle also told Business Insider that “the FTC has a complete picture of Amazon’s decision-making in this case including 1.7 million documents from sources like email, internal messaging applications, and laptops (among other sources), and over 100 terabytes of data.”