WI American Girl Headquarters Set to Close News | February 16, 2024 | 0 | by Morgan McCarthy American Girl is closing its headquarters in Middleton. The company yesterday said about 30 people will lose their jobs in the move. Some of those people will be working their last day today, while others will stay on the job til September. Mattel, which owns American Girl, says the decision to close the Middleton office is part of a move to centralize their operations in their new California headquarters. American Girl was founded in Middleton in 1986. Mattel bought American Girl in 1998.