The US Securities and Exchange Commission has filed an enforcement action against Institutional Shareholder Services, Inc. (ISS) in federal court, alleging that the proxy advisory giant has refused to produce documents demanded under a subpoena issued more than four months ago. The case was filed on September 4, 2026, in the US District Court for the Eastern District of Pennsylvania.

ISS is one of the two dominant proxy advisory firms — alongside Glass Lewis — that influence how institutional shareholders vote on matters ranging from executive compensation packages to board elections. The firm's recommendations carry weight because many asset managers, pension funds, and index funds rely on ISS guidance when casting votes on behalf of millions of retail investors, giving the duopoly a concentrated role in corporate governance outcomes at US public companies.

What the SEC Is Seeking

The dispute dates back to March 2026, when the SEC's Division of Examinations opened a review of ISS's operations. The review is focused on whether the firm's proxy recommendations and voting activities comply with federal securities laws. Because ISS is registered as an investment adviser, it falls squarely within the SEC's regulatory jurisdiction — a status the commission has previously reinforced through rule amendments governing proxy voting advice.

On July 21, 2026, the SEC formalized its demand by issuing an administrative subpoena requiring the production of relevant documents. According to the SEC's filing, ISS has "unreasonably refused" to produce those documents, despite multiple attempts by the agency to resolve the matter without litigation. Enforcement actions of this kind — seeking judicial enforcement of an administrative subpoena — typically precede any findings of wrongdoing, and a court order compelling compliance can carry penalties for continued non-compliance.

The SEC's court filing seeks a judicial order compelling ISS to comply. The agency has explicitly stated that its underlying review has not yet determined whether any violations actually occurred.

Why Proxy Advisory Firms Are Under Scrutiny

ISS has previously drawn the SEC's attention. In 2013, the firm settled with the commission, paying a $300,000 penalty in connection with the improper sharing of confidential information, and was required to retain a compliance consultant.

The current subpoena targets what the SEC describes as critical operational data tied to ISS's core business model, including internal methodologies, communications regarding specific proxy recommendations, and compliance records. The outcome of the subpoena fight may shape how much regulatory visibility the SEC gains into the internal processes of proxy advisers, an industry whose recommendations have long drawn debate over transparency and potential conflicts of interest — including ISS's own proxy voting business, which operates alongside its advisory recommendations.