CHICAGO (CBS) — The City Club of Chicago announced late Sunday that its office was subpoenaed and issued a warrant by a federal grand jury earlier this year.

The subpoena and warrant were issued in mid-May, the City Club said.

“The City Club of Chicago has fully cooperated with the government’s request for information and documents. City Club is not the subject of an investigation; rather, it is one of many entities and individuals who have been served to provide information,” the City Club said in a news release. “The City Club of Chicago has not had any further requests since its last production in July.”

The City Club did not offer any further specifics about the investigation in which it was asked to provide information.

The City Club of Chicago is a public affairs forum that brings in speakers for discussions about public affairs. The nonprofit was founded in 1903.