Under the transaction, Souls Private Equity will increase its stake in the insurance broker and risk management firm to 40 per cent.
"InterRisk has proven its ability to compete against the global broking giants. We are looking forward to being part of their exciting future," Souls Private Equity general manager Andrew Fairfull said.
The insurance broker plans to implement an acquisition strategy.
"[Souls Private Equity's] boosted commitment to our organisation represents a new chapter for InterRisk," InterRisk chair David Wills said.