New Mountain Capital has completed a growth investment in audit, assurance, tax and advisory services provider Grant Thornton to help the latter expedite its current business strategy.

Investment companies CDPQ and OA Private Capital also made minority investments in Grant Thornton along with New Mountain Capital.

New Mountain Capital managing director Andre Moura said: “We continue to be impressed by the Grant Thornton team and their unwavering focus on delivering the highest levels of quality and client experience.

“In this next chapter, we look forward to partnering with the team to invest even further in people, technology and new service line capabilities to accelerate the growth trajectory Grant Thornton is already on.”

Based in the US, Grant Thornton is the brand for two professional-services entities, namely Grant Thornton LLP and Grant Thornton Advisors. The first entity is a licensed, certified public accounting (CPA) firm that provides audit and assurance services.

Grant Thornton Advisors exclusively offers non-attest offerings, including tax and advisory services.

The new growth investment is also expected to help Grant Thornton strengthen its position as the industry’s platform of choice.

Grant Thornton Advisors CEO Seth Siegel said: “Partnering with New Mountain Capital, CDPQ and OA Private Capital will empower us to accelerate our winning strategy, benefit our clients and team members, and solidify our position as the industry’s platform of choice for the next 100 years.”

Headquartered in New York, New Mountain Capital currently manages private equity, credit and net lease investment strategies with about $50bn in assets under management.

Guggenheim Securities and Jefferies served as financial advisers to New Mountain Capital while Deutsche Bank Securities served as sole financial adviser to Grant Thornton.