BRUSSELS (Reuters) -Brazil's antitrust enforcer CADE has opened an investigation into Microsoft, days after Norwegian browser Opera complained about Microsoft's Edge, according to a CADE statement published late Thursday on its website.

Opera, in its complaint filed on Tuesday, alleged that Microsoft pre-installs Edge as the default browser across Windows devices and computers, thereby preventing rivals from competing on the merits of the products.

Opera had 6.78% of the Brazilian desktop browser market in June versus Edge's 11.52% and market leader Google Chrome's 75%.

CADE said it had opened an administrative inquiry and set an August 15 deadline for Microsoft to respond to Opera's allegations about its Windows operating system licences, the Microsoft 365 software and its Jumpstart programme.

The Jumpstart programme allows Microsoft clients to build autonomous artificial intelligence agents for routine tasks, a move which could help the company monetise its billion-dollar investments in AI. Other Big Tech companies have similar tools.

Microsoft did not immediately respond to emailed requests for comment.

Opera has been complaining about its competitor since December 2007 when it took its grievance about the latter's internet Explorer browser bundled with its Windows operating system to the European Commission, resulting in a 561-million-euro ($640 million) fine for the U.S. tech giant.

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