Willdan Group, Inc. Announces Agreement to Acquire Mantis for $285M

What Happened
Willdan Group, Inc. (WLDN) filed an 8-K reporting that its wholly owned subsidiary, Willdan Energy Solutions, Inc., entered into a Membership Interest Purchase Agreement dated September 22, 2026 to acquire 100% of Mantis Intermediate Holdings, LLC from Mantis NewCo, LLC. The base cash purchase price is $285,000,000, subject to customary post-closing adjustments. The Purchase Agreement is included in the filing as Exhibit 2.1.

Key Details

• Base purchase price: $285,000,000 in cash, subject to adjustments for working capital, cash on hand, unpaid indebtedness and transaction expenses.
• Closing timing: scheduled for October 30, 2026 (or the third business day after closing conditions are satisfied or waived).
• Buyer protections and obligations: Willdan unconditionally guarantees all of Energy Solutions’ obligations under the Purchase Agreement, including payment of the adjusted purchase price and financing obligations.
• Financing and risk allocation: Energy Solutions is required to use reasonable best efforts to obtain debt financing per a Debt Commitment Letter; Energy Solutions has arranged representations-and-warranties insurance to cover certain seller breaches (subject to policy terms).

Why It Matters
This is a material acquisition agreement for Willdan: the $285M base price and the fact that Willdan guarantees the buyer’s obligations mean the transaction could affect Willdan’s balance sheet, financing needs and credit exposure depending on how the deal is funded and final purchase price adjustments. The closing is contingent on regulatory clearance (including Hart-Scott-Rodino review), satisfaction of reps-and-warranties/covenants, and other customary conditions, so the transaction is not final until those conditions are met. Investors should watch subsequent filings for details on financing terms, any purchase price adjustments, and any disclosed financial impact or pro forma results.