The Jersey-based agency will become part of the private equity firm’s value demonstration business. : Arsenal Capital Partners purchased Guidemark Health, the private equity firm said on Tuesday. It bought out the stake held by previous private equity partner Highroad Partners. The purchase price is undisclosed, and there are no layoffs associated with the acquisition. Guidemark CEO Michael Parisi will report to Julia Ralston, global practice lead for Arsenal's medical strategy and communications practice.