Chicago-based investment firm Ariel Investments said it purchased copies of Mayor Catherine Pugh’s “Healthy Holly” books to distribute to attendees at a 2013 leadership conference where she was speaking.

Ariel purchased 400 copies of the book for $3,680, including $80 in shipping fees, through Associated Black Charities. It was the only Healthy Holly donation Associated Black Charities took where the organization did not retain any of the donation for itself.

Pugh, then a state senator, was one of about 17 speakers at the October 2013 Black Corporate Directors Conference in California, sponsored by Ariel.

Ariel typically purchases the books of speakers at the conference, said Wendy Fox, the firm’s chief compliance officer.

Most books are for adults, but other books purchased for attendees have included John Lewis’ graphic novel adaptation of his autobiography, Fox said.

Fox did not know the topic of Pugh’s speech.

Last year, the city Board of Estimates, where Pugh controls three of the five votes, approved a $40 million investment of Employees’ Retirement System funds with Ariel that included $272,000 in annual fees.

Ariel was winner of a search that included four finalists and was selected by the retirement system’s board of trustees.

Fox said there was no way it could have known in 2013 that Pugh was even thinking about running for mayor.