Kaspersky Lab says that Microsoft is abusing its dominance in the PC operating system market, creating obstacles for independent software security vendors by distributing its own Defender anti-virus software with the ubiquitous Windows operating system.
Microsoft said in a statement on Tuesday that it had not violated any laws.
"Microsoft's primary objective is to keep customers protected," the company said in an emailed statement. "We are confident that the security features of Windows 10 comply with competition laws. And we will answer any questions regulators may have."
Kaspersky filed the complaints after the two companies failed to resolve their differences through private negotiations.
Kaspersky in November threatened to complain to the European Commission but in April said it would hold off because Microsoft had agreed to make some changes.
"These actions by Microsoft lead to a lower level of protection for users, a limitation on their right to choose, and financial losses both for users and security solutions manufacturers," Kaspersky said on Tuesday.
The European Commission confirmed it had received Kaspersky's complaint without giving further details.
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