Microsoft Mobile Oy is the name of Microsoft's future handset division.
When the acquisition of Nokia's business is complete, the group will remain in Finland and be called Microsoft Mobile Oy, according to leaked documents. The word "Oy" is Finnish that mean something like "LLC." or "Corp."
It's also Yiddish for "ouch," but it's likely Microsoft has the Finnish one in mind.http://www.ubergizmo.com/2014/04/nokias-phone-division-will-be-named-microsoft-mobile/