UPMC — Pittsburgh’s largest employer and largest owner of tax-exempt property — will give the city $10 million to purchase new ambulances, Mayor Corey O’Connor announced Thursday morning. Former Mayor Ed Gainey, who served from 2022 until Jan. 5, tried taking major nonprofits including UPMC to court to revoke tax exemptions on certain properties, including major hospitals. UPMC responded not with a major gift but with terse statements saying they would participate in a contribution to the city if other major nonprofits stepped up simultaneously. UPMC alone was exempt from nearly $14 million annually in city property taxes that would be due if it was a for-profit entity. City Controller Rachael Heisler, who took office after the 2022 report was produced, hailed the $10 million gift as a “significant investment” in a written statement Thursday.