NLIGHT INC

UNITED STATES

SECURITIES AND EXCHANGE COMMISSION

Washington, D.C. 20549

SCHEDULE 14A

PROXY STATEMENT PURSUANT TO SECTION 14(a) OF THE

SECURITIES EXCHANGE ACT OF 1934

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NLIGHT, INC.

(Name of Registrant as Specified In Its Charter)

(Name of Person(s) Filing Proxy Statement, if other than the Registrant)

High power lasers for mission critical aerospace & defense and advanced manufacturing applications

2025 Annual Meeting

Proxy Statement and Notice of Annual Meeting

NOTICE OF ANNUAL MEETING OF STOCKHOLDERS

To Be Held at 9:00 a.m. Pacific Time on Tuesday, June 10, 2025

Dear Stockholders of nLIGHT, Inc.:

We cordially invite you to attend the 2025 annual meeting of stockholders (the “Annual Meeting”) of nLIGHT, Inc., a Delaware corporation, which will be held on Tuesday, June 10, 2025, at 9:00 a.m. Pacific Time. This year’s Annual Meeting will be a completely virtual meeting of stockholders. You can attend the Annual Meeting by visiting www.virtualshareholdermeeting.com/LASR2025 where you will be able to listen to the meeting live, submit questions and vote online. We are holding the Annual Meeting for the following purposes, as more fully described in the accompanying proxy statement:

1. To elect the Class I director nominees named in the accompanying proxy statement to serve until the 2028 annual meeting of stockholders and until their respective successors are duly elected and qualified;

2. To ratify the appointment of KPMG LLP as our independent registered public accounting firm for our fiscal year ending December 31, 2025;

3. To approve, on an advisory, non-binding basis, the compensation of our named executive officers; and

4. To transact such other business that may properly come before the Annual Meeting or any adjournments or postponements thereof.

Our board of directors has fixed the close of business on April 14, 2025, as the record date for the Annual Meeting. Only stockholders of record on April 14, 2025, are entitled to notice of and to vote at the Annual Meeting. Further information regarding voting rights and the matters to be voted upon is presented in the accompanying proxy statement.

Important Notice Regarding the Availability of Proxy Materials for the Annual Meeting to Be Held on Tuesday, June 10, 2025. On or about April 25, 2025, we expect to mail to our stockholders a Notice of Internet Availability of Proxy Materials (the “Notice”) containing instructions on how to access our proxy statement and annual report. The Notice provides instructions on how to vote via the Internet, telephone or mail (if you receive printed proxy materials) and includes instructions on how to receive a paper copy of our proxy materials. The accompanying proxy statement and our annual report can be accessed directly at the following Internet address: www.proxyvote.com. All you have to do is enter the control number located on your Notice or proxy card.

YOUR VOTE IS IMPORTANT. Whether or not you plan to attend the Annual Meeting, we urge you to submit your vote via the Internet, telephone or mail as soon as possible. We appreciate your continued support of nLIGHT.

By order of the Board of Directors,

President and Chief Executive Officer

Camas, Washington

April 25, 2025

To Our Stockholders,

For over 25 years, nLIGHT has been at the forefront of high-power laser innovation, enabling next-generation applications once thought impossible. As a pioneering provider of high-power lasers for mission critical defense systems and advanced manufacturing, we leverage our vertically integrated technology stack to continue to push the boundaries of laser power and precision, ensuring maximum effectiveness across a wide range of evolving applications.

2024 was a year of important milestones for nLIGHT. Revenue from aerospace & defense grew to more than 60% of our total sales in the fourth quarter, and this market has become our primary growth driver. To support our transition to a more aerospace & defense-oriented business, we completed the final steps in a multi-year process of de-risking important parts of our manufacturing process including ramping manufacturing at our automated facility in the United States and qualifying a third-party contract manufacturer in Thailand to support our commercial business. As a US-based pure-play high-power laser provider, we believe we are uniquely positioned to address the U.S. Department of Defense’s most critical priorities.

Defense Takes Center Stage

Interest in our directed energy lasers continues to grow as ongoing military operations in the Middle East and Ukraine highlight the increasing need for advanced, cost-effective defensive weapons technology. Directed energy lasers offer a deep magazine, low cost per engagement, and speed-of-light delivery to counter a wide range of threats – including drones, rockets, artillery, mortars and missiles.

nLIGHT has been a leader in the development of high-power lasers for directed energy for over two decades, incorporating patented and proprietary technologies across our entire technology stack from semiconductor laser diodes to high-power fiber amplifiers, beam-combined lasers, and beam directors and have established ourselves as the most comprehensive supplier to the U.S. government, other prime contractors and foreign allies.

In 2024 we continued to execute on several of our key Directed Energy programs. We began delivering key components for the High Energy Laser Scaling Initiative (“HELSI”) - a U.S. Department of Defense $171 million program to develop a 1-megawatt high-energy laser with a completion date expected in 2026. We finalized designs and delivered key components for a $34 million dollar contract to deliver a 50-kilowatt high-energy laser to the U.S. Army’s Directed Energy Maneuver-Short Range Air Defense program. The success we have achieved to date in these key programs reinforces the capability of our technology and our commitment to this market. Outside of the United States, interest in directed energy lasers also continues to increase. As an example, in October, Israel announced that it would spend over $500 million dollars toward Iron Beam, an Israeli ground-based laser system for defense against aerial threats including rockets, mortars, drones, and missiles.

We also continued to gain momentum in our Laser Sensing markets in 2024. Our laser sensing products include missile guidance, proximity detection, range finding and countermeasures, and have been incorporated into several significant and long-running defense programs, all of which remain key defense priorities. During 2024, we announced a new $25 million dollar contract for an existing long-running missile program. We’ve also continued to make excellent progress on several classified programs that are expected to transition to low-rate initial production in 2025.

Aligned our Commercial Opportunities to Support Long-term Growth

2024 was another challenging year for our commercial markets as a growing number of our customers faced increased competition from China and global manufacturing demand remained muted. With these headwinds expected to continue, we completed our manufacturing transition out of China, reallocated critical engineering resources into defense, and refocused and rationalized our investments within our commercial markets to the highest growth opportunities, such as metal additive manufacturing.

We continue to realize strong synergies between our commercial and defense technologies and markets. For example, our proprietary laser diodes are the fundamental building blocks for both our commercial lasers and our high energy directed energy lasers and these capabilities have enabled us to lead the world with the highest demonstrated power of over 300 kW.

Moreover, in metal additive manufacturing we are benefiting directly from our deep engagement in the aerospace & defense markets. Several of our aerospace & defense customers are actively implementing metal additive manufacturing to accelerate prototyping timelines, build resiliency into their supply chains and create durable domestic manufacturing capabilities for next generation munitions and unmanned aerial vehicles.

2024 Financial Summary

Revenue from our aerospace & defense markets grew 20% year-over-year and represented more than 55% of total revenue, up from 44% last year. Offsetting this growth was a decline in our commercial markets. We continue to monitor our operating expenses and capital outlays closely and we have reallocated resources to areas of the business that are aligned with our long-term growth objectives. Our balance sheet remains strong, with over $100 million of cash and investments, and we believe we possess the financial flexibility to fund our near-term operations while positioning ourselves to benefit from the long-term opportunities we see in the aerospace & defense markets. Finally, we ended the year with $167 million of funded backlog, an increase of 55% compared to December 31, 2023, and we are executing against contracts with $399 million of aggregate value.

Looking Forward

In summary, 2024 was an important year for nLIGHT with significant milestones achieved, particularly in our aerospace & defense markets, where revenue grew to more than 60% of our total fourth quarter sales and established itself as the primary growth driver for our business going forward. We completed the last leg of our manufacturing transition out of China and are now operationally set to support the growth expected in our defense business.

As I look forward, I am most optimistic about growth in aerospace & defense as we are well aligned with key priorities for the Department of Defense, we have a large and growing backlog, and we have a strong balance sheet. I am optimistic that the significant progress that we made in 2024 will accelerate in 2025 and position us for long term growth.

I want to thank our employees whose hard work and commitment continue to propel our company forward. And we sincerely thank you, our valued stockholders, for your continued support and confidence in our company. Together, we are shaping the future of laser technology.

Sincerely,

Co-Founder, Chief Executive Officer, and Chairman of the Board

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