ANAHEIM, Calif.–(BUSINESS WIRE)—- $WLDN–Willdan Group, Inc. (NASDAQ: WLDN) announced today that it has completed the previously announced acquisition of Mantis Intermediate Holdings, LLC (“Mantis”), doing business as Mantis Innovation, for $285 million in cash, subject to customary holdbacks and adjustments. The transaction closed following expiration of the applicable waiting period under the Hart-Scott-Rodino (“HSR”) Antitrust Improvements Act and satisfaction of customary closing conditions. Headq