Can anyone challenge my design patent? How?

You submit an application for a patent to the U.S. Patent and Trademark Office. It includes a complete description of your invention or design which the USPTO publishes on its web site. Any one who has a similar invention/design or thinks that there is prior art that would prevent a patent on the invention/design has a designated period of time to submit an objection to the issuance of a patent to you and the reasons why. The USPTO then has to decide if your idea is sufficiently unique to issue a patent or if there is valid reason to refuse to do so. A patent can also be challenged after it is issued via a law suit filed in federal court.

Your new design must be ornamental, new, and not-obvious in view of previous designs - the "prior art." The Patent Office may reject your design upon initial review - but you can argue why they are wrong. A competitor may later challenge your design patent in the Patent Trial and Appeal Board - yesterday Luv n' Care Ltd. urged the full Federal Circuit to review its first America Invents Act decision on a design patent, arguing the appellate court wrongly upheld an unfair Patent Trial and Appeal Board decision that a design for a baby drinking cup was unpatentable. Good Luck!