The nation’s largest pension has mostly divested itself of tobacco and related stocks, but “Calpers” recently bought Tilray stock. : This copy is for your personal, non-commercial use only. To order presentation-ready copies for distribution to your colleagues, clients or customers visit http://www.djreprints.com. The California Public Employees’ Retirement System, the biggest pension fund in the U.S., won’t invest in tobacco companies. But apparently it doesn’t have an issue with marijuana producers.