The New York City-based audio entertainment company Sirius XM Holdings disclosed in a regulatory filing Friday that Patrick Donnelly is retiring after serving as general counsel since May 1998.

The filing said his current employment agreement expires Friday and will not be renewed. Instead, the parties have negotiated a transition agreement under which the 63-year-old will remain general counsel until April, when he'll transition to a part-time role running through year-end under which he'll help facilitate the transition to his successor. The company has not yet selected that person.