LONDON: Macquarie Asset Management, together with co-investors including UniSuper, has agreed to acquire a majority stake in SI Solutions, a leading provider of structural integrity engineering, testing and software solutions to critical infrastructure owners and operators, from private equity fund MidOcean Partners.

The transaction is expected to close in fall 2026, subject to regulatory approvals and customary closing conditions.

SI Solutions specializes in determining whether critical, high-consequence assets are safe, compliant and fit for continued service. Its engineers and technicians evaluate remaining useful life through stress, fatigue and materials analysis, diagnose the root cause of equipment and system performance issues, and apply that expertise across the full asset lifecycle, from design and construction through operation and life extension. The work is supported by advanced non-destructive evaluation, laboratory testing, failure analysis and asset management software.

The company’s expertise in structural integrity was first developed serving the power generation sector, where safety and reliability are critical, and now extends across nuclear, gas power, pipeline, petrochemical, civil and industrial markets. Headquartered in Huntersville, North Carolina, SI Solutions operates from 16 locations, five of which include testing laboratories, and currently supports more than 330 clients.

The platform was built by integrating specialist firms with long-established technical track records, allowing SI Solutions to apply its combined engineering, testing and software capabilities across a diverse client base.

Macquarie Asset Management said it sees significant growth opportunity for SI Solutions driven by structural tailwinds across the infrastructure sector, particularly in the power generation markets in which the company specializes. The investment follows Macquarie Asset Management’s strategy to invest in high-quality, stable businesses that provide critical services, products and technologies to infrastructure end-markets.

“SI is a highly regarded industry leader with a strong track record of serving many of the largest utilities, who seek out SI for their most challenging structural integrity problems,” said Andrew Olinick, senior managing director at Macquarie Asset Management. “SI’s specialization in the power generation markets is a strong fit for our strategy.”

Alec Rubenstein, managing director at Macquarie Asset Management, said SI Solutions embodies several of the firm’s highest conviction investment themes, including the convergence of energy and digital infrastructure, the need to keep aging critical infrastructure safe and in service, and the role of clean, reliable power generation such as nuclear.

“We see significant opportunities to accelerate growth by leveraging our deep industry expertise and network, and we are excited to support SI in its next phase of expansion,” Rubenstein said.

Mark W. Marano, president and CEO of SI Solutions, said the company is pleased to partner with Macquarie Asset Management and its co-investors.

“Their deep sector expertise and long-term investment approach are an ideal fit for SI,” Marano said. “We look forward to working with them on the next phase of our growth story as we capitalize on the momentum in the nuclear and gas power markets to further our leadership position in structural integrity.”

Sandra Lee, head of private markets at UniSuper, said SI Solutions offers a compelling opportunity to deliver long-term value for members while supporting the critical infrastructure that underpins reliable power generation.

“We are pleased to deepen our partnership with Macquarie Asset Management and invest in a proven, high-quality business with specialized capabilities that keep essential energy assets safe, compliant and operating at the highest standards,” Lee said.

Macquarie Asset Management is a global asset manager that manages US$498 billion in assets, according to figures as of March 31, 2026. It is part of Macquarie Group, a diversified global financial services group founded in 1969 that employs more than 19,100 people in 30 markets and is listed on the Australian Securities Exchange.

UniSuper is one of Australia’s largest superannuation funds and is run for the benefit of its members. It currently invests approximately A$175 billion on behalf of approximately 688,000 members. Its A$20 billion private markets portfolio includes direct investments across transport and logistics, digital infrastructure, healthcare, essential services and sustainable real assets.