Apple has been granted a patent so vague it may never be able to use it.

The patent covers the outer shape of a device - a rectangle with rounded corners.

The design is defined by a single line marking the shape of its original iPad.

The US Patent and Trademark Office issued patent no. D670,286 to the company on Monday.

The patent does not cover other features of the iPad's hardware, including the home button and the size and shape of the bezel. As The Verge explains, it really does just cover the solid edge line of the design.

Apple has frequently taken to court to defend the design and patents covering its iPad and other devices. But it hasn't always been successful: a recent UK High Court decision found that while Samsung's Galaxy tablets were similar in some respects (while being, according to the judge, 'not as cool'), they did not infringe on the iPad's design. The company was later forced to publish what amounts to an apology for asserting that Samsung copied its design.

It is unlikely that Apple would be able to rely on this patent in future court cases, because it is just so broad. But then again, when it comes to Apple and the legal system you shouldn't be surprised by anything...