Pedestrians walk near the U.S. Patent and Trademark Office (USPTO) headquarters in Alexandria, Virginia, U.S., on Friday, April 4, 2014. The Senate Judiciary Committee tomorrow plans to mark up a measure that would curb the activities of so-called patent trolls after pulling back the bill last week in the face of opposition from such companies as 3M Co., AstraZeneca Plc, Monsanto Co. and Procter & Gamble Co. Photographer: Andrew Harrer/Bloomberg via Getty Images