📄 What This Document Is 🏛️

This is a Joint Proxy Statement/Prospectus, filed on April 21, 2026. Think of it as a single, comprehensive packet designed to inform both CECO and Thermon stockholders about a massive, complex transaction: the proposed merger between the two companies. Because this document is so detailed, it covers everything from the mechanics of the deal to the specific votes required at two upcoming shareholder meetings.

👉 Why it matters: This document doesn't just report on a merger; it is a mandatory voting guide. Reading it carefully is crucial because your vote is required to approve the merger and to elect board members.

🏢 What The Companies Do 🌍

Before the merger can happen, it is essential to understand the companies involved. CECO Environmental Corp. is described as a leading, diversified industrial company that specializes in environmental solutions. They provide critical systems and technology across several industries, including product recovery, air pollution control, fluid handling, and filtration.

• CECO Environmental Corp.: Provides customized systems and technology to protect people, the environment, and industrial equipment across a broad, global customer base.
  • Why it matters: CECO is the acquiring company, establishing it as a major player in industrial environmental services.
• Thermon Group Holdings, Inc.: The filing indicates that detailed information about Thermon and its subsidiaries is incorporated by reference, meaning they have their own comprehensive background information that the reader can access in the full document.
  • Why it matters: Thermon is the company being acquired and will cease to exist as a separate entity upon the completion of the deal.

🤝 The Two-Step Merger Plan ⚙️

The deal is not a simple merger; it is a structured, two-step process that dictates the legal sequence of the acquisition. The goal is for CECO to acquire Thermon.

• First Merger: Longhorn Merger Sub Inc., a wholly owned subsidiary of CECO, will merge with and into Thermon. After this step, Thermon will survive only as a wholly owned subsidiary of CECO.
• Second Merger: Immediately following the first merger, the surviving Thermon entity will merge with and into Longhorn Merger Sub LLC, which becomes the ultimate surviving company.
  • Why it matters: This complex structure is a standard way to handle large corporate acquisitions, allowing CECO to assume complete control of Thermon's assets and operations seamlessly.

💰 Merger Consideration & Payment 💵

This section details exactly what Thermon stockholders will receive for their shares. Instead of a single payout, the merger allows stockholders to choose from three options, which are then filtered through a complex "proration" process.

• The Three Election Choices (Per Share of Thermon Common Stock):
  • Mixed Consideration (Default): This package consists of 0.6840 shares of CECO common stock plus $10.00 in cash. This option is crucial because it is not subject to proration, meaning it is the guaranteed consideration.
  • Cash Election: Stockholders can elect to receive $63.89 in cash per share.
  • Stock Election: Stockholders can elect to receive 0.8110 shares of CECO common stock per share.
• The Proration Mechanism: Because the total amount of cash and stock needed for all elective choices might exceed the company's planned budget, the payment is "capped."
  • Cash Cap: The total cash paid is capped at approximately $334 million, which is calculated as $10.00 multiplied by the total number of Thermon shares outstanding.
  • Stock Cap: The total CECO shares are capped at approximately 22.9 million shares, calculated as 0.6840 multiplied by the total number of Thermon shares outstanding.
  • Impact: If too many stockholders choose cash (or stock), those electing cash/stock will receive a prorated portion (a proportional share) of their election, with the remaining value paid in the other form (stock for cash, or cash for stock).
  • Why it matters: The default Mixed Consideration is the only guaranteed amount, while the chosen Cash and Stock amounts may be significantly reduced if the overall demand is too high.

🏛️ CECO Stockholder Vote Requirements 🗳️

As a CECO stockholder, you must vote at the Annual Meeting on several key items that allow the merger to proceed. The board strongly recommends voting "FOR" all proposals.

• CECO Stock Issuance Proposal: You must vote to approve the issuance of shares of CECO common stock to Thermon stockholders. This approval is a condition for the merger's closing.
• CECO Director Election Proposal: You will vote to elect eight directors.
• CECO Say-on-Pay Proposal: This is an advisory vote on the compensation of CECO’s named executive officers. While non-binding, the board recommends voting "FOR" this proposal.
• CECO Equity Plan & Auditor Ratification: You will vote to approve the 2026 Equity Plan and to ratify the appointment of Deloitte & Touche LLP as the independent registered public accounting firm.
  • Why it matters: The CECO board believes that voting "FOR" these proposals is necessary to advance the overall merger and ensure the company's governance structure is stable.

🧑‍⚖️ Thermon Stockholder Vote Requirements 📜

As a Thermon stockholder, your vote at the Special Meeting is critical to the acquisition. The board strongly recommends voting "FOR" all proposals.

• Thermon Merger Proposal: You must vote to adopt the merger agreement. This approval is a condition for the merger's closing.
• Thermon Compensation Proposal: This is an advisory vote on compensation for Thermon's named executive officers related to the merger.
• Adjournment Proposal: A simple vote to adjourn the meeting if necessary.
  • Why it matters: The vote to adopt the merger agreement is the primary decision point; without a majority vote on this proposal, the acquisition cannot close.

⚠️ Major Risks & Considerations 🚨

The joint proxy statement dedicates substantial space to listing the risks, which is very important reading for any stockholder. These risks highlight potential hurdles to the success of the combined company.

• Integration Risk: The combined company might struggle to integrate Thermon’s business and operations into CECO's. This includes difficulties like merging disparate IT systems, harmonizing corporate cultures, and realizing expected cost savings (synergies).
• Market Price Fluctuation Risk: The stock portion of the merger consideration is fixed by an exchange ratio (0.8110 shares of CECO common stock) but is not adjusted for the market price of CECO stock before closing. A decline in CECO’s stock price could mean the stock consideration is worth much less than the cash consideration ($63.89).
• Legal & Tax Risk: The merger is structured to qualify as a "reorganization" for tax purposes. If the IRS or a court determines that the deal does not qualify as a reorganization, stockholders could face substantial U.S. federal income taxes.
• Trading Restriction: If you elect any form of consideration, your shares are restricted and cannot be sold or transferred until the merger closes, which may be a period of several weeks.
  • Why it matters: These risks caution that the expected benefits and integration plans are not guaranteed, and the cash-flow implications could be complex.

🗓️ Meeting Details and Logistics 📍

For stockholders to exercise their rights, they must participate in the respective meetings.

• CECO Annual Meeting: Scheduled for May 27, 2026, at 8:00 a.m., Central Time. It will be held virtually.
  • CECO Record Date: Stockholders must own CECO common stock as of the close of business on April 17, 2026.
• Thermon Special Meeting: Scheduled for May 27, 2026, at 8:00 a.m., Central Time. It will also be held virtually.
  • Thermon Record Date: Stockholders must own Thermon common stock as of the close of business on April 20, 2026.
• Key Contact Information:
  • CECO Proxy Solicitor: D.F. King & Co., Inc. (Toll-free: (800) 515-4507, E-mail: [email protected]).
  • Thermon Proxy Solicitor: Innisfree M&A Incorporated (Toll Free: (877) 717-3905).

---

🧠 The Analogy

The merger of CECO and Thermon is like one major bookstore (CECO) deciding to buy out a smaller, specialized bookstore (Thermon). To make the deal official, the owners of the smaller store must vote to sell their inventory (shares) and agree to the new management structure. Because the deal is huge, the payment for the inventory isn't a single price; it's an auction with three options—cash, or stock, or a mix—and the total cash and stock paid out are capped to ensure the final payment mix fits the new budget.

🧩 Final Takeaway

This document confirms that CECO is acquiring Thermon via a two-step merger. Stockholders must carefully review the details of the three potential payment options, understand the critical proration mechanics, and participate in the mandated votes at the virtual meetings on May 27, 2026, for the transaction to close.