WASHINGTON — President Trump has picked Joseph J. Simons, a veteran antitrust lawyer who has represented tech giants like Microsoft, to lead the Federal Trade Commission at a time of broad bipartisan concern over corporate consolidation and big deals in the waiting, the White House said Thursday.

Mr. Trump has also chosen Noah Phillips, chief counsel for Senator John Cornyn, Republican of Texas, and Rohit Chopra, a fellow at a consumer advocacy group, to fill the remaining two seats at the agency, said Natalie M. Strom, assistant press secretary at the White House.

The consumer protection and competition agency has been led by just two commissioners over the last 10 months. Mr. Trump’s other leading antitrust official, Makan Delrahim, was recently confirmed to lead competition cases at the Justice Department.

The timing of the official nominations is unclear. They will be reviewed by Congress but are expected to be approved.