$21 billion Google announced that Arthur Levinson has resigned as a member of the company's board of directors, effective immediately.

The departure of the former Genentech CEO follows increased regulatory scrutiny by the Federal Trade Commission over his membership as a director of both Google's board, of which Levinson has been a member since April 2004, and Apple's board. The board relationship between Apple and Google—both considered Microsoft rivals—are being investigated by the FTC over anti-competitive concerns.