Portillo's was acquired by the prominent private equity investment firm Berkshire Partners, which purchased a controlling majority stake in the restaurant chain from its founder, Dick Portillo. Under Berkshire Partners' private equity stewardship, the brand expanded its operational footprint significantly before executing an initial public offering on the NASDAQ stock exchange. Even following its transition into a publicly traded corporation, the private equity firm retained substantial equity ownership, gradually reducing its stake through secondary public offerings over subsequent years.