While there is a long history of opposition to sensible marijuana policy reform from some big pharmaceutical companies, September saw the biggest financial donation from such a company against a legalization ballot initiative to date, and their motives couldn't be more blatant. According to campaign finance reports, the committee formed to oppose Prop. 205, Arizonans for Responsible Drug Policy, received a $500,000 contribution on August 31 from Insys Therapeutics, Inc. According to a CNBC investigative…