Microsoft has re-ignited speculation that a subscription-based version of Windows is in the works after registering the trademark 'Windows 365'.
First spotted by Neowin, the filing dated January 29 is listed under "computer software; computer operating system software; network operating software; computer programs; aforementioned goods".
Just as Office 365 was launched as a subscription-based alternative to the desktop-based version of Office, the idea of a cloud-based version of Windows accessible for an annual fee has floated around for some time.
At the launch of Windows 10, Microsoft's Terry Myerson said that the company plans to offer "Windows as a Service", raising the possibility that of a subscription-based offering.
However, as he explained in a company blog post and reiterated in an interview to TechRadar Pro, this referred to free, continous upgrades to the platform rather than an entirely new way of charging for the OS.
With Microsoft increasingly shifting its products to subscription-based services, the idea of a constantly updated and backed-up Windows paid for annually begins to make sense.
But with Windows 10 yet to launch as a free upgrade for Windows 7 and Windows 8 users for one year, it's difficult to see a subscription-based version of Windows gaining any traction in the near future.