Turns out that for Apple Inc., being one of the most innovative companies on the planet does have at least one big drawback. The Cupertino, Calif., company says it is the No. 1 target for so-called patent trolls. In court and regulatory filings, Apple provided a rare look at the amount of litigation it is facing from companies whose main business involves threatening to file patent lawsuits against other companies unless they agree to make royalty payments.