Kaspersky Lab has filed an anti-trust complaint with the European Commission against Microsoft.

The cyber security company alleges that Microsoft is abusing its market dominance by pushing Windows 10 users to its own anti-virus software – Windows Defender.

The company claims that Microsoft’s: “dominant position in the computer operating system (OS) market to fiercely promote its own – inferior – security software (Windows Defender).”

Read more: Exploring Antarctica with Eugene Kaspersky: From art and penguins, to the Glaciator robot

Kaspersky said: “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 solution manufacturers.”

The claim is not just in defence of Kaspersky’s products but of all third-party security software.

Microsoft’s response has been to say that its security features “comply with competition laws” and it said that it would answer all the regulators questions.

Read more: Trump cybersecurity executive order prompts review of Kaspersky software

A Microsoft spokesperson said: “Microsoft’s primary objective is to keep customers protected and we are confident that the security features of Windows 10 comply with competition laws. We’re always interested in feedback from other companies and we engage deeply with antimalware vendors and have taken a number of steps to address their feedback. We reached out directly to Kaspersky a number of months ago offering to meet directly at an executive level to better understand their concerns, but that meeting has not yet taken place.”

The Russian company’s original complaint against Microsoft had been filed with Russia’s Federal Anti-monopoly Service last year, but has now been filed with the European commission and the German Federal Cartel Office.