The chief legal officer of Los Angeles-based AECOM is resigning, according to a recent Securities and Exchange Commission filing.

Carla Christofferson and AECOM have "mutually agreed" in the Nov. 29 filing that she will continue working with the infrastructure company as a "non-executive employee" until Dec. 16. During that time, she will continue to receive her annual salary. Under the terms of her separation agreement, she will receive a cash severance payment equal to her annual base salary, a monthly COBRA payment for up to 12 months, and 41,342 shares of the company's common stock in respect of certain unvested company equity awards.

Carla Christofferson. Carla Christofferson.

"We thank Carla for her many contributions during her time at AECOM and wish her well in her future endeavors," the company said in a statement.

Christofferson could not be reached for comment Tuesday. The reason for her departure is not clear, and it is not clear who will be taking over her role on either an interim or permanent basis. The filing was signed by David Gan, the senior vice president and deputy general counsel at AECOM.

She joined the AECOM in March 2015 as its top lawyer. Before joining AECOM, she was a partner at O'Melveny & Myers in Los Angeles. She was hired by O'Melveny in 1993 after graduating from Yale Law School.

Christofferson is leaving just before a new CEO is named. According to a November SEC filing, the company's CEO, Michael Burke, will resign from his post when the board of directors finds a CEO or prior to the company's 2020 annual meeting in March.

It is not clear whether Burke's impending resignation is connected to Christofferson's resignation.