TriNet Group Inc.'s board added Michael Angelakis as a member, expanding its size to 10 directors.

Angelakis' appointment was part of a stockholder agreement related to Atairos Group's purchase of an approximately 26% ownership stake in TriNet, which closed Feb. 1. Angelakis is chairman and CEO of Atairos Group.

The board designated Angelakis as a class III director.