App developers could have their apps booted from all Microsoft marketplaces if they remain unpatched more than six months after vulnerabilities have been disclosed.
The policy effective immediately would boot apps from Microsoft's distribution platforms: Windows Store, Windows Phone Store, Office Store, and Azure Marketplace.
Microsoft Trustworthy Computing spokesman Dustin Childs said apps under active exploitation could be pulled offline sooner.
"In those cases, we'll work with the developer to have an update available as soon as possible and may remove the app from the store earlier."
Childs said Microsoft would help developers patch their apps if they were unable to issue a fix by the deadline.
"To date, no apps have come close to exceeding this deadline."
Microsoft's deadline followed a decision by Google in May which gave developers a week to patch critical issues under active exploitation
But Microsoft's new policy appears to be the first company that hosts mobile app stores to act in this way.