The Securities and Exchange Commission's inspector general has launched a formal investigation to determine if the agency was justified in leasing 900,000 square feet at D.C.'s Constitution Center, according to sources familiar with the investigation. The office is investigating the August lease as well as the agency's decision this month to move 740 employees and contractors by September from two Alexandria facilities to space the agency is leasing in the District, the sources said. The 10-year Constitution Center lease was inked for $44.80 a square foot with a 1 percent escalation a year. The inspector general's office declined to confirm or deny the investigation, citing agency policy.

The lease, the largest federal lease in a decade, came under fire shortly after it was announced as critics both inside the agency and out questioned its sheer size and noted that the SEC still had vacant offices at its Station Place headquarters near Union Station.