A design patent is a form of intellectual property protection which allows an inventor to protect the original shape or surface ornamentation of a useful manufactured article. This applies to any unique form or otherwise perceivable design features of an object - for instance, a chair, table, hand tool, clock, bottle or purse.
Whether an invention falls under the scope of a design patent can be a tricky question. There are two basic criteria for eligibility:
The design must be industrial. Thus, a painting or sculpture is not eligible for design patent protection because it is not separable from a useful object.
The design must not be dictated by the function of the article. That is, if the design specifically affects the way the article works, that design would not be separable from function and would not be eligible for design patent protection (though it may be eligible for a utility patent).
Like all patents, a design patent is a right to exclude. That is, it gives the owner the right to exclude others from making, using, selling, offering to sell or importing articles with the particular design without permission. And design patent rights can be enforced in federal courts. Design patents last for 14 years, with no maintenance fees required.