Michael McGinnis, president of auction house Phillips, is leaving the company after 16 years as the smaller rival to Christie’s and Sotheby’s undergoes a transformation under new senior management.

McGinnis will step down on Nov. 30 to spend time with his family and pursue other opportunities, Phillips said Thursday in an e-mailed statement. After founding the contemporary-art department in 1999, McGinnis became the boutique auctioneer’s chief executive officer in 2012 and held the post until CEO Edward Dolman’s arrival in 2014, when he assumed his current role.