The U.S. International Trade Commission will take a second look at the patent infringement lawsuit between Motorola and Apple. The agency, which has the power to block imports of the iPhone, plans to review Judge Thomas Pender’s findings that invalidated Motorola’s patent for a proximity sensor that prevents accidental hang-ups. The judge ruled in December that Motorola’s patent wasn’t substantially different from a previous invention that prevented accidental dialing, but the company argued that the earlier invention concerned physical keys and not touchscreens. The invalidation cleared  Apple (AAPL) of Motorola’s infringement claims. The Commission’s six-member panel will review the initial ruling and make a final decision on April 22nd.