Proto Labs Inc

Cautionary Note Regarding Forward-Looking Statements

This proxy statement contains forward-looking information within the meaning of the Private Securities Litigation Reform Act of 1995 that is subject to certain risks and uncertainties that could cause actual results to differ materially from those projected, expressed, or implied by such forward-looking information. Risks and uncertainties that could cause or contribute to such differences include, but are not limited to, those discussed in Item 1A, “Risk Factors” included in our Annual Report on Form 10-K for the fiscal year ended December 31, 2024, as may be updated in our subsequent Quarterly Reports on Form 10-Q. To the extent permitted under applicable law, Proto Labs, Inc. assumes no obligation to update any forward-looking statements as a result of new information or future events.

PROXY SUMMARY

This Proxy Summary provides general information about Proto Labs, Inc. (the “Company” and "Protolabs") and highlights certain information contained elsewhere in this Proxy Statement. As it is only a summary, please refer to the entire Proxy Statement and the Annual Report on Form 10-K for the year ended December 31, 2024 before you vote. The Proxy Statement and accompanying materials were first provided to shareholders on or about April 9, 2025.

2024 HIGHLIGHTS

2024 was a transformational year for Protolabs, delivering strong financial results, including expanded gross margins, increasing non-GAAP earnings per share, and growing our cash flow from operations to $77.8 million, up from $73.3 million in 2023. During 2024, Protolabs continued the evolution beyond prototyping into production, and we reorganized our internal structure, creating regional go-to-market teams and a new global operations organization. Our go-to-market teams are refocused to ensure the best possible customer experience from prototype to production, while our operations

organization efficiently brings our global fulfillment capabilities to every customer.

Our transformation is gaining meaningful traction from both new and existing customers. In 2024, the number of customers using our combined Factory and Network offer grew by 50% and revenue per customer increased over 2023. We are making strategic investments to drive growth, including additional marketing to build our brand as a production manufacturer, allocating resources to improve our sales enablement tools and processes, and continuing to expand our production manufacturing capabilities.

DIRECTOR NOMINEES

Chairperson

Member

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CORPORATE GOVERNANCE HIGHLIGHTS

•Separate Board Chairperson and CEO

•Risk oversight by full Board and Committees

•Majority voting standard for uncontested director elections

•Annual election of directors

•Bylaws provide for Proxy Access by shareholders

•Annual advisory say-on-pay vote

CORPORATE RESPONSIBILITY AND SUSTAINABILITY HIGHLIGHTS

Our corporate responsibility and sustainability practices are built on a foundation of shared fundamental values. In 2024, we updated our value statements to: We are one Team, We are Kind, We are Makers, We Win or We Learn and We Take Ownership. These values help us to deliver strong financial results that create value for our Company and our shareholders in a way that respects our communities and the environments in which we operate.

•We are one Team – We are one global team. We're successful when we work together, challenge one another, and make decisions that support our common goals. We are authentic in our interactions.

•We are Kind – We are clear with our words and actions. We seek and give thoughtful and constructive feedback delivered with respect. We're open to other's opinions and support decisions made.

•We are Makers – Whether we manufacture a part or provide a customer experience, we demonstrate excitement in our work. We embrace change and create space for experimentation and calculated risks.

•We Win or We Learn - We're dedicated to achieving our goals. When we fail, we learn and respond with resiliency. When we win, we share in celebration.

•We Take Ownership - We take pride in our work. We are enthusiastic about the impact we make on our employees, our customers, and the communities we serve.

Environmental

•Digital Manufacturing Drives Sustainability

As a digital manufacturer, we are able to assist our customers as they focus on materials management, operational productivity and on-demand solutions. Digital manufacturing is a solution our customers can deploy to reduce product waste by iterating part designs virtually, on a digital twin model before any actual production begins. With on-demand production of parts, there is also reduced reliance on storage facilities since inventory is virtual – the parts you need,

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when you need them. Our on-demand manufacturing model also helps customers with end-of-life planning for products, reducing the need for ordering excess parts with shifting market demand.

When paired with a robust e-commerce platform, digital manufacturing can also increase efficiencies in material selection and usage, the procurement process, and accelerate innovation. Furthermore, reducing scrap rate requires monitoring systems that enable automated process cycle sheet generation, ensuring run-to-run repeatability and reducing operator error. This kind of monitoring system can improve consistency in part production and reduce scrap costs, especially in injection molding and parts nonconformance. We believe sustainability in product development, and in manufacturing, is the future and we will continue to support our customers in their own sustainability journeys.

•Environmental Priorities

We are committed to having a positive impact on the environment. Our environmental key priorities include: nonrenewable energy use reduction and environmental compliance. In 2024, we devoted resources to manage increasing costs of energy, particularly in the European region, and sought opportunities to reduce our consumption of energy resources. We also embraced opportunities to shift our energy consumption to renewable resources.

In 2024, we again hosted InspirON in Europe, an online knowledge sharing event to focus on what design engineers need to consider when developing sustainable products for manufacturing. The event was designed to provide insight into designing more sustainable products and to explore how design can help make the manufacturing process greener and more efficient. The event covered topics ranging from: manufacturing innovation in the face of adversity, using rapid manufacturing to solve complex development challenges, and practical innovation for production methods.

In 2021, we were awarded a Manufacturing Leadership Award from the National Association of Manufacturers (NAM) in the Sustainability Leadership category. This category recognizes companies embracing manufacturing processes that are non-polluting, conserve energy and natural resources, and are economically sound and safe for employees, communities, and consumers. In 2020, we installed nearly 1,900 solar panels on the roof of our facility in Plymouth, MN, one of our larger manufacturing facilities. The solar array covers nearly 20 percent of our energy use in Plymouth, MN and offsets the equivalent of 1.3 million pounds of CO2 and preserves 775 acres of forest annually.

We strive to maximize recycling in both our manufacturing and office facilities. In our manufacturing facilities, we recycle metal, plastic and water used throughout the manufacturing processes. Finally, the Green Team, an employee-led organization, educates our employees on how they can positively impact the environment, both at work and at home. The Green Team also provides opportunities for employees to positively impact the environment, including activities like roadside cleanup and tree planting.

Social

•Leadership

In 2024, our global human resources leadership advanced our initiatives to identify untapped talent as we continue to integrate operations of the factory and network. This work includes engaging employees throughout the global organization to define our values and culture, which we deployed in 2024. We periodically conduct employee engagement surveys to identify and drive improvements in the Protolabs work place where employees are engaged and can do their best work.

•Workforce Demographics

As of December 31, 2024, we had 2,357 full-time employees, including 1,643 full-time employees in the United States and 714 full-time employees in Europe. We also regularly use independent contractors and other temporary employees across the organization to augment our regular staff. We believe that our future success will depend in part on our continued ability to attract, hire, and retain qualified and inclusive personnel with diverse backgrounds.

We believe our employees are critical to our success and continually seek employee feedback to enhance employee engagement. In 2024, our attrition rates were 12.2% and 12.9% in the United States and Europe, respectively, each of which was a decline from 2023. Our 2024 attrition rates were impacted by actions we took during the year to reduce our workforce in areas of the business that experienced lower volumes.

•Compensation and Benefits

We believe our success depends in large measure on our ability to attract, retain and motivate a broad range of employees to be successful in a dynamic and changing business environment, and that a competitive compensation program is essential. In determining employee compensation, our executive leadership team reviews and considers several factors, including individual and corporate performance, input from managers, competitive market data from third party compensation surveys, our compensation philosophy and key principles, and the leadership’s collective experience and knowledge. Annually, our executive leadership team reviews input from managers throughout our organization, including recommendations as to compensation levels that the managers believe are commensurate with an individual’s job performance, skills, experience, qualifications, criticality to our Company and development/career

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opportunities. We also award long-term equity-based compensation to high performing employees and managers who have the greatest impact on the creation of shareholder value to further align the interests of our employees and shareholders.

We provide employee benefits that meet or exceed the requirements of local law. We are committed to providing comprehensive benefits plans including, but not limited to, paid leave, retirement savings, health benefits, dental benefits, maternity leave, parental leave, family care leave, and childcare benefits. All overtime is performed and compensated in accordance with the law and the individual’s employment contract or other applicable contract or collective agreement.

•Education

We firmly believe that investing in the education of our employees is critical to our success. Our employees are provided access to a robust learning management system that offers hundreds of courses on various topics ranging from compliance to leadership to job-specific skills. In 2024 and 2023, employees spent an average of 35 hours per employee in training sessions. We provide an Educational Assistance Program for employees, which offers financial assistance for both professional and personal development to inspire employees to continuously enhance their skills and knowledge. We have a customized leadership development program designed for current and aspiring managers in search of developing their leadership skills. The program provides training on topics that are aligned with our Leadership Principles and our Core Values. In 2024, we completed the second year of our mentorship program to provide opportunity for mentors and mentees to accelerate their personal and professional development through a one-on-one guided relationship.

To ensure our industry remains robust, we are committed to supporting Science, Technology, Engineering and Mathematics ("STEM") programs in the cities where we have facilities. Through the Protolabs Foundation, we provide STEM education grants to eligible organizations. In addition, we partner with schools, colleges, and universities to provide various outreach opportunities and sponsorships.

•Health, Safety and Wellness

We are committed to providing a safe and healthy working environment that minimizes health and safety risks. Our processes support accident prevention and prioritizes the health and safety of all our employees and all others affected by their activities. We provide and require our employees to use personal protective equipment at all times. To ensure our employees understand the importance of safety, we provide regular, mandatory training.

We strive to continuously improve our employees’ health, safety, and wellness. Our “I Am” safety program teaches that safety is the responsibility of every individual in our organization. We believe this program is the basis for our excellent safety compliance record. We believe that our employees are our most valuable asset, and their safety and health is among our top priorities.

In addition to concentrating on employee safety in the workplace, we also focus on the overall wellbeing of our employees. We continue to invest in a variety of employee health and wellness programs, including gym membership discounts, on-site fitness classes at certain facilities, wellness newsletters and learning sessions, and by providing various Employee Assistance Programs.

•Charitable Giving

We pride ourselves in being a responsible corporate citizen through our Protolabs Foundation. We support several charitable causes with our Employee Matching, Good Ideas Grants, and Major Gifts Programs. The Foundation’s efforts serve as a sustaining investment in the future of the communities where our employees live and work, and a commitment to build talent to support the future employment needs of the manufacturing industry. Through our Protolabs Foundation and employee led community involvement team, a wide variety of charitable activities are organized, including blood drives, working for Habitat for Humanity projects, volunteering for Feed My Starving Children, and making financial contributions to charitable causes, many of which are matched through the Protolabs Foundation Employee Giving Program. Our financial support and our community outreach programs are intended to improve the quality of life in the communities where we have facilities.

•Human Rights

We recognize our responsibility to protect human rights and we are committed to fostering an organizational culture which promotes support for internationally recognized human rights and labor standards. We strive to respect and promote human rights in accordance with the UN Guiding Principles on Business and Human Rights in our relationship with our employees, customers, and suppliers. We have established a Human Rights Policy which is available on the Investor Relations section of our website.

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•Supply Chain

We are committed to conducting our business in accordance with the highest ethical standards and in compliance with all applicable laws, rules, and regulations. We expect our suppliers to share our principles and uphold our standards and for each to develop policies and programs as appropriate to ensure that all workers understand and adhere to these standards. We have established a Vendor Code of Conduct Policy, including guidance on anti-bribery, privacy, and data protection; responsible sourcing of materials; environmental standards; labor and human rights and anti-tax evasion. Our full policy is available on the Investor Relations section of our website.

OUR COMPENSATION APPROACH

We believe our success depends in large measure on our ability to attract, retain and motivate a talented senior management team to effectively lead our Company in a dynamic and changing business environment, and that a competitive executive compensation program is essential to that effort. We believe that our executive compensation program should support our short- and long-term strategic and operational objectives, and reward corporate and individual performance that contributes to creating value for our shareholders.

Consistent with this philosophy, and past practice, the majority of our named executive officers’ 2024 summary annual compensation is considered "at risk".

2024 Summary Annual Compensation

AGENDA ITEMS AND BOARD RECOMMENDATIONS

Unless you give other instructions on your proxy card, the persons named as proxy holders on the proxy card will vote in accordance with the recommendations of our board of directors. Each of the below proposals are described in more detail in this Proxy Statement:

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PROXY STATEMENT

The Board of Directors of Proto Labs, Inc. is soliciting proxies for use at the Annual Meeting to be held on May 20, 2025, and at any adjournment or postponement of the meeting.