US Attorney General Eric Holder has named Renata Hesse acting head of Justice Department's Antitrust Division to replace departing chief Joseph Wayland. Hesse was the lead lawyer in the remedies phase of DOJ's antitrust suit against Microsoft and she also involved in trying to stop Oracle from acquiring PeopleSoft, the start of its great takeover binge. She was a partner at the famed Silicon Valley law firm Wilson Sonsini Goodrich & Rosati PC after leaving the government in 2006. Last year she joined the Federal Communications Commission and reviewed AT&T's proposed $39 billion acquisition of T-Mobile, which ultimately fell to objections. She returned to the DOJ in March as special adviser for civil enforcement and deputy assistant attorney general. The Obama White House picked William Baer to head the division, but the Senate has yet to vote on the nomination. Senate Judiciary Committee Republicans have suggested something turned up in his background check.