Atwell Partners with Advent International to accelerate next phase of growth

• Investment will support the continued growth of an engineering services market leader

Southfield, MI, and Boston, MA, March 27, 2026 - Advent International ("Advent"), a leading global private equity investor, today announced that it has agreed, in partnership with management, to make a significant investment in Atwell, LLC ("Atwell" or the "Company"), a leading provider of engineering, consulting, and construction services to critical infrastructure in the United States. Advent's investment will help accelerate the Company's future growth ambitions, benefitting customers and creating opportunities for the Company's 2,000 professionals.

Founded in 1905 and headquartered in Southfield, Michigan, Atwell brings a longstanding legacy of technical expertise and quality service delivery to a nationwide customer base across Power & Energy, Community Development, and Commercial & Digital Infrastructure. The Company is recognized as a leading employer in the industry with an award-winning culture.

Advent will partner with the existing Atwell management team to support the Company's next phase of growth. Together, the parties plan to build on Atwell's strength by investing in talent and technology, expanding geographic reach, and growing service capabilities. The investment will also support Atwell's team members by enabling expanded investment in corporate services, digital platforms, and operational infrastructure designed to enhance collaboration, efficiency, and project delivery across the organization.

"Atwell has built a strong reputation for delivering high-quality engineering and consulting solutions to clients across the U.S.," said Jason Karl, Managing Director at Advent International. "We believe the Company is exceptionally well positioned to benefit from long-term growth drivers such as infrastructure investment, energy transition tailwinds, and an underbuilt housing market. We look forward to partnering with the talented Atwell team to help accelerate growth and expand the platform to even more areas throughout the country."

"Atwell's growth has always been driven by our people and their commitment to delivering exceptional results for our clients and communities," said Matthew Bissett, President and Chief Executive Officer of Atwell. "We believe Advent's global resources, deep sector expertise, and track record of supporting growth-oriented businesses make them an ideal partner for Atwell. With their support, we are excited to continue investing in our people, innovation, and capabilities while delivering even greater value to our clients."

This investment brings together Advent's deep experience investing across the professional services and industrials sectors. Since 2020, the firm has invested over $8 billion in 22 business and financial services companies and over $12 billion in 14 industrials companies across a wide range of sub-sectors as of December 31, 2025. Prior relevant investments include Culligan International, Fisher Investments, Heidrick & Struggles, Imperial Dade, LayerZero Power Systems, and Nuvei Corporation.

The transaction is expected to close in the second quarter of 2026, subject to customary regulatory approvals and closing conditions.

Advisors

Goldman Sachs & Co. LLC is serving as exclusive financial advisor and Wachtell, Lipton, Rosen & Katz is serving as legal counsel to Atwell. Morrissey Goodale LLC is serving as a strategic advisor to the Company. Morgan Stanley & Co. LLC is serving as exclusive financial advisor and Weil, Gotshal & Manges LLP is serving as legal counsel to Advent.

About Atwell

Atwell, LLC is a full-service consulting, engineering, and construction services firm delivering innovative solutions for clients in community development, commercial, digital infrastructure, power and hydrocarbon markets. The Company provides a comprehensive range of services including planning and entitlement, land and right-of-way solutions, surveying, engineering, environmental consulting, GIS and mapping, and construction management. Founded in 1905 and headquartered in Southfield, Michigan, Atwell supports clients across the United States through a multidisciplinary platform designed to advance complex infrastructure and development projects. For more information, visit https://www.atwell.com.

About Advent International

Advent is a leading global private equity investor committed to working in partnership with management teams, entrepreneurs, and founders to help transform businesses. With 16 offices across five continents, we oversee more than USD $102 billion in assets under management* and have made 448 investments across 44 countries.

Since our founding in 1984, we have developed specialist market expertise across our five core sectors: business & financial services, consumer, healthcare, industrial, and technology. This approach is bolstered by our deep sub-sector knowledge, which informs every aspect of our investment strategy, from sourcing opportunities to working in partnership with management to execute value creation plans. We bring hands-on operational expertise to enhance and accelerate businesses.

As one of the largest privately-owned partnerships, our 655 colleagues leverage the full ecosystem of Advent's global resources, including our Portfolio Support Group, insights provided by industry expert Operating Partners and Operations Advisors, as well as bespoke tools to support and guide our portfolio companies as they seek to achieve their strategic goals.

To learn more, visit our website or connect with us on LinkedIn.

*Assets under management (AUM) as of December 31, 2025. AUM includes assets attributable to Advent advisory clients as well as employee and third-party co-investment vehicles.

Media Contacts

For Atwell:
Timothy J. Augustine
Chief Corporate Officer
[email protected]

For Advent:
Lauren Testa
[email protected]