Glass, Lewis & Co. (Glass Lewis)[2] is a major American proxy advisory services company. As of spring 2019, Glass Lewis controlled 28% of the proxy advisory market for mutual funds; this makes it the second-largest company in the market behind Institutional Shareholder Services.[3][4] The primary services provided by Glass Lewis are research and recommendations for shareholder votes by institutional investors, including a digital platform for managing these votes and reporting.[3][4] A large fraction of those investors follow the recommendations of Glass Lewis in lockstep, giving it outsize importance and impact on governance across the corporate sphere.[5]