The Securities and Exchange Commission will host a public roundtable on Dec. 5 to discuss the services proxy advisory firms provide for institutional investors and investment advisers.

The roundtable, held at the SEC's Washington, D.C. headquarters, will be open to the public as well as webcast live. Information on the time, agenda and participants will be issued shortly, Tuesday's announcement of the roundtable said.

The announcement comes amid renewed scrutiny of, and longstanding concerns about the proxy advisory firms retained to provide recommendations that assist investors and investment advisers in voting on matters presented to shareholders. Some proxy advisory firms also provide consulting services, including to publicly traded companies they may make recommendations about. Critics say this dual role, as well as the ownership of proxy advisory services, can pose conflicts of interest.

Institutional Shareholder Services, owned by MSCI Inc., and Glass Lewis, owned by the Ontario Teachers' Pension Plan Board and Alberta Investment Management Corp., control approximately 97 percent of the market for proxy advisory services

The role of proxy advisory firms was among the issues the SEC explored in a 2010 concept release on the proxy voting system. The release sought public comment on potential conflicts of interest and transparency in the proxy advisory industry. The Dec. 5 roundtable is intended to provide a forum to discuss these issues.

The meeting comes at an interesting time for the two top proxy advisors. It was announced earlier this month that  MSCI, a public company traded on the New York Stock Exchange, authorized the “exploration of strategic alternatives” regarding ISS and could sell the subsidiary. MSCI bought ISS in 2010.

Also, last month, citing concerns that proxy advisory firms “not only increase the costs of being a public company, but also create disincentives for companies to become public in the first place,” Nasdaq OMX Group petitioned the SEC for new disclosure and transparency demands on how those firms formulate their recommendations.

The petition requests that the SEC revise guidance issued nearly ten years ago and demand disclosure of the models, formulas and methodologies used to make recommendations on how shareholders should vote. Disclosure is also urged for “all relationships that may give rise to conflicts of interest.”

Earlier this year, the European Securities and Markets Authority, after seeking comment on the proxy advisory industry, issued a report in which it called for a code of conduct for the proxy advisory industry. The Canadian Securities Administrators, an umbrella group of Canada's securities regulators, recently announced that it expects to propose a regulatory approach to proxy advisory firms in early 2014.