Citing multiple sources, Bloomberg is reporting that the EU will launch a “full-blown” antitrust investigation of Amazon this week.

“Amazon.com Inc. faces a full-blown European Union antitrust probe as the bloc’s competition chief Margrethe Vestager prepares for a summer finale to her five-year crackdown on U.S. technology giants,” the report notes, perhaps a bit too breathlessly. “[Vestager] is poised to open a formal investigation into Amazon within days, according to two people familiar with the case, who asked not to be named because the process isn’t public.”

An antitrust investigation into Amazon is no surprise: Vestager has been hinting for months that the online retailing giant is a target.

“[Amazon] host a lot of little guys, and at the same time, they’re a big guy in the same market,” Vestager has said. “So how do they treat the data that they get from the little guy? Does that give them an advantage that cannot be matched?”

Vestager has also aggressively targeted—and fined and sanctioned—other U.S. tech giants, like Google and Apple, that trample on the EU’s antitrust and privacy laws. And it plans similar investigations into Facebook, Qualcomm, and other companies.

But this investigation is a bit different from previous EU antitrust action. It’s also different from previous Amazon cases, as the firm has run into trouble for evading taxes and stifling the market for ebooks. This time, it’s about Amazon’s retail business model. And if the EU does act—and let’s face it, of course it will—then it could lead to dramatic changes in how Amazon operates.