RSG chairman and CEO Patrick G. Ryan said in a statement that Mr. Rice, who joined RSG in 2010, had cultivated RSG Underwriting Managers from a start-up to one of the world’s largest collections of managing general underwriters, with more than $160 million in revenues.

Mr. Rice has also served as a member of Ryan Specialty Group’s board of directors.

No replacement for Mr. Rice has been named, according to a spokeswoman.