{"filing":{"accession_number":"0001104659-26-110002","cik":"0001370450","ticker":"WLDN","company_name":"Willdan Group, Inc.","form":"8-K","filing_date":"2026-09-23","report_date":"2026-09-22","primary_document":"tm2625947d1_8k.htm","primary_document_url":"https://www.sec.gov/Archives/edgar/data/1370450/000110465926110002/tm2625947d1_8k.htm"},"events":[{"id":34630,"run_id":31871,"accession_number":"0001104659-26-110002","anchor_item_number":"1.01","event_type":"ma_activity","event_domain":"operational","is_material":true,"confidence":0.98,"summary":"Willdan Group's wholly owned subsidiary Energy Solutions entered into a Membership Interest Purchase Agreement on September 22, 2026, to acquire 100% of Mantis Intermediate Holdings, LLC for a base purchase price of $285 million in cash. This is a material acquisition transaction disclosed under Item 1.01, with a scheduled closing of October 30, 2026, subject to customary closing conditions including HSR antitrust clearance and debt financing. The transaction size and strategic nature make it material to investors.","company_name":"Willdan Group, Inc.","ticker":"WLDN","filing_date":"2026-09-23","form":"8-K","submitted_at":null,"items":[{"id":38412,"accession_number":"0001104659-26-110002","item_number":"1.01","item_title":"Entry into a Material Definitive Agreement","event_type":"ma_activity","event_domain":"operational","is_material":true,"confidence":0.98,"reasoning":"Willdan Group's wholly owned subsidiary Energy Solutions entered into a Membership Interest Purchase Agreement on September 22, 2026, to acquire 100% of Mantis Intermediate Holdings, LLC for a base purchase price of $285 million in cash. This is a material acquisition transaction disclosed under Item 1.01, with a scheduled closing of October 30, 2026, subject to customary closing conditions including HSR antitrust clearance and debt financing. The transaction size and strategic nature make it material to investors.","classifier_version":"claude-haiku-4-5-20251001+prompt-a85dd512","taxonomy_version":"v1.3","classified_at":"2026-09-23T20:34:53.263424+00:00","company_name":"","ticker":null,"filing_date":""}]}],"classifications":[{"id":38412,"accession_number":"0001104659-26-110002","item_number":"1.01","item_title":"Entry into a Material Definitive Agreement","event_type":"ma_activity","event_domain":"operational","is_material":true,"confidence":0.98,"reasoning":"Willdan Group's wholly owned subsidiary Energy Solutions entered into a Membership Interest Purchase Agreement on September 22, 2026, to acquire 100% of Mantis Intermediate Holdings, LLC for a base purchase price of $285 million in cash. This is a material acquisition transaction disclosed under Item 1.01, with a scheduled closing of October 30, 2026, subject to customary closing conditions including HSR antitrust clearance and debt financing. The transaction size and strategic nature make it material to investors.","classifier_version":"claude-haiku-4-5-20251001+prompt-a85dd512","taxonomy_version":"v1.3","classified_at":"2026-09-23T20:34:53.263424+00:00","company_name":"Willdan Group, Inc.","ticker":"WLDN","filing_date":"2026-09-23"}]}