Nokia has never flat out denied that the company has a Windows-based tablet in the works. The company's CEO Stephen Elop has hinted in a number of interviews that such a product is in the works.
Now, it has been discovered that Nokia has filed for two different design patents for a tablet-like product with the United States back in March 2011. Both of the patents have now been discovered by NokiaPowerUser.com.
One of the designs has more of a curved shape in its case, much like that of Nokia's Lumia smartphone products.
The other design seems to have a more traditional shape for a tablet.
Both of these designs were likely in the works well before Nokia and Microsoft announced their partnership to release Windows Phone-based smartphones in early 2011. However, it still shows that Nokia was thinking about releasing some kind of tablet and it's more that possible that the company could adapt one or even both of these designs to run either Windows 8 or Windows RT.
It seems like, in terms of a tablet from Nokia, it's really not a question of "if" anymore but "when" and when the official announcement is indeed made, it will likely run on some kind of Windows-based OS.
Source: NokiaPowerUser.com | Image via Nokia