Amherst-based Prometheus Books has sold its publishing assets to Rowman & Littlefield Publishing Group of Maryland.
The sale price was not disclosed.
Prometheus operated independently since its founding in 1969 by the late philosopher Paul Kurtz. The company has a backlist of 1,700 active titles published under the Prometheus and Humanity Books imprints, according to Publishers Weekly.
Last November, Prometheus sold its fantasy and crime novel imprints to Start Publishing to focus on its nonfiction books.
Jonathan Kurtz, Paul's son and Prometheus' president, and editor Jake Bonar will remain under the company's new ownership, R&L said.
Kurtz did not respond to a request for comment on the reason behind the sale and its effect on the Amherst workforce.
The trade titles published under Prometheus' imprint will continue to be released under the Prometheus name as part of R&L’s Globe Pequot division. The titles published through Humanity Books will be distributed by R&L's academic and professional division.