The JOBS Act was designed to make it easier for startups to raise money through an initial public offering. But a lesser-noticed provision has made it more difficult to determine what those companies are paying their general counsel and other executives.

The federal Jumpstart Our Business Startups Act, which marks its second anniversary this month, includes a provision that allows companies to disclose less about executive compensation. According to a comprehensive survey of the rules’ impact on company behavior undertaken by Latham & Watkins, 85 percent of qualifying companies have taken advantage of this aspect of the rules.