Princeton Equity Group, a private equity firm focused on control investments in franchisor, completed the acquisition of a minority stake in Ellie Mental Health, an operator and franchisor of outpatient mental health clinics. Financial terms were not disclosed. "The partnership with Princeton will help facilitate the next chapter of our growth as we rapidly expand our corporate and franchise businesses. This investment could not have come at a more opportune time given the country's mental health crisis and the inaccessibility of quality mental health treatment," Erin Pash, Ellie Founder.