The land rush for mobile patents is so feverish that about one-quarter of all patents issued in the U.S. this year will be mobile-related, according to a study released on Wednesday. "It just shows, given the number of filings, how competitive that space has become," said Chetan Sharma, founder and president of Chetan Sharma Consulting. He studied statistics about patent applications and grants in Europe and the U.S. over the past 20 years. Sharma's study didn't consider the significance of the patents.