"He and his team have set the PTO on course to implement the key provisions of the Act, which will improve the patent system for decades to come," Sen. Patrick Leahy (D-Vt.) said in a statement. "I was sad to hear of his decision to step down; the President and the Commerce Department have lost a valuable member of their economic team."
Kappos has credited the law with helping to clear some of the Patent Office's backlog of applications.
He has defended the patent system from critics who claim that software patents are too easy to obtain, sparking widespread legal battles.
Kapps did not announce what he plans to do when he leaves office, and the White House has yet to name a successor. Teresa Stanek Rea is the office's deputy director.