WASHINGTON — Firms that advise institutional investors and other market participants on how to vote at annual shareholder meetings will be regulated more closely following a vote by the Securities and Exchange Commission on 22 July.

Companies have long complained that so-called proxy advisers wield outsize influence over the votes of shareholders, who often park their money in mutual funds or exchange-traded funds rather than buy shares directly. Asset managers, in turn, rely on proxy advisers in making voting decisions, with some using software to automatically fill ballots with their voting recommendations.