FUEL TECH, INC.

Previous wording

Customers may cancel or delay projects for reasons beyond our control. Our orders normally contain cancellation provisions that permit us to recover our costs, and, for most contracts, a portion of our anticipated profit in the event a customer cancels an order. If a customer elects to cancel an order, we may not realize the full amount of revenues included in our backlog. If projects are delayed, the timing of our revenues could be adversely affected and projects may remain in our backlog for extended periods of time. Revenue recognition occurs over long periods of time and is subject to unanticipated delays. If we receive relatively large orders in any given quarter, fluctuations in the levels of our quarterly backlog can result because the backlog in that quarter may reach levels that may not be sustained in subsequent quarters.

Current wording

Revenue recognition occurs over long periods of time and is subject to unanticipated delays. If projects are delayed, the timing of our revenues could be adversely affected and projects may remain in our backlog for extended periods of time. If we receive relatively large orders in any given quarter, fluctuations in the levels of our quarterly backlog can result because the backlog in that quarter may reach levels that may not be sustained in subsequent quarters. Customer-driven delays may also lead to increased material costs and other adverse financial impacts.

Previous wording

A small number of customers have historically accounted for a significant portion of our revenues. During 2024, our five largest customers accounted for approximately 49% of our net revenues, with our largest customer accounting for approximately 16% of our net revenues. There can be no assurance that all significant customers will continue to purchase our products in the same quantities that they have in the past. The loss of any one of our significant customers or a material reduction in sales to a significant customer could have a material adverse effect on our sales and results of operations.

Current wording

A small number of customers have historically accounted for a significant portion of our revenues. During 2025, our five largest customers accounted for approximately 58% of our net revenues, with our largest customer accounting for approximately 21% of our net revenues. These five customers contributed revenues to the FUEL CHEM business segment during 2025. There can be no assurance that all significant customers will continue to purchase our products in the same quantities that they have in the past. The loss of any one of our significant customers or a material reduction in sales to a significant customer could have a material adverse effect on our sales and results of operations.

Previous wording

We hold licenses to or own a number of patents for our products and processes. In addition, we also have numerous patent applications pending both in the U.S. and abroad. There can be no assurance that any of our pending patent applications will be granted or that our outstanding patents will not be challenged, overturned or otherwise circumvented by competitors. In foreign markets, the absence of harmonized patent laws makes it more difficult to ensure consistent respect for our patent rights in emerging markets. In addition, certain critical technical information relating to our products which is not patented is held as trade secret, and protected by trade secret laws and restrictions on disclosure contained in our confidentiality and licensing agreements. There can be no assurance that such protections will prove adequate or that we will have adequate remedies against contractual counterparties for disclosure of our trade secrets or other violations of our intellectual property rights. See Item 1 above under the caption*“Intellectual Property.”*

Current wording

We hold licenses to or own a number of patents for our products and processes. We also have patent applications pending both in the U.S. and abroad. There can be no assurance that any of our pending patent applications will be granted or that our outstanding patents will not be challenged, overturned or otherwise circumvented by competitors. In foreign markets, the absence of harmonized patent laws makes it more difficult to ensure consistent respect for our patent rights in emerging markets. In addition, certain critical technical information relating to our products which is not patented is held as trade secret, and protected by trade secret laws and restrictions on disclosure contained in our confidentiality and licensing agreements. There can be no assurance that such protections will prove adequate or that we will have adequate remedies against contractual counterparties for disclosure of our trade secrets or other violations of our intellectual property rights. See Item 1 above under the caption*“Intellectual Property.”*

Previous wording

Our FUEL CHEM technology segment is dependent, in part, upon a supply of magnesium hydroxide. Any adverse changes in the availability of this chemical will likely have an adverse impact on ongoing operation of our FUEL CHEM programs. On March 4, 2009, we entered into a Restated Product Supply Agreement (PSA) with Martin Marietta Magnesia Specialties, LLC (MMMS) in order to assure the continuance of a stable supply from MMMS of magnesium hydroxide products for our requirements in the U.S. and Canada. The term of the PSA expires on December 31, 2025. Pursuant to the PSA, MMMS supplies us with magnesium hydroxide products manufactured pursuant to our specifications and we have agreed to purchase from MMMS, and MMMS has agreed to supply, 100% of our requirements for such magnesium hydroxide products for our customers who purchase such products for delivery in the U.S. and Canada. There can be no assurance that we will be able to obtain a stable source of magnesium hydroxide in markets outside the U.S.

Current wording

Our FUEL CHEM technology segment is dependent, in part, upon a supply of magnesium hydroxide. Any adverse changes in the availability of this chemical will likely have an adverse impact on the ongoing operation of our FUEL CHEM programs. On March 4, 2009, we entered into a Restated Product Supply Agreement (PSA) with Martin Marietta Magnesia Specialties, LLC (MMMS) in order to assure the continuance of a stable supply from MMMS of magnesium hydroxide products for our requirements in the U.S. and Canada. The PSA is renegotiated annually. Pursuant to the PSA, MMMS supplies us with magnesium hydroxide products manufactured pursuant to our specifications and we have agreed to purchase from MMMS, and MMMS has agreed to supply, 100% of our requirements for such magnesium hydroxide products for our customers who purchase such products for delivery in the U.S. and Canada. There can be no assurance that we will be able to obtain a stable source of magnesium hydroxide in markets outside the U.S.