The investment trust appointed Campbell Lutyens as an independent broker.
The UK accountancy group is reportedly valued at more than £1 billion, with Penta retaining management of the asset after abandoning an earlier sale.
A non-binding term sheet also gives O3 the option to increase its ownership in the Hungarian fund manager if AUM grows significantly.
The single-asset vehicle for Dutch technical services provider VDK saw investors representing more than 40% of EMK Fund I's capital elect to roll over.
The partnership will also develop products for wealth investors, beginning with an evergreen private equity secondaries fund expected in the coming weeks.
The portfolio and single-fund sales included stakes in US-based credit funds with 2019-2022 vintages.
Montana Capital Partners was the sole buyer of a collection of 15 private equity fund interests across Europe and North America.
At least 80% of net proceeds from the transaction will be directed toward a share buyback program aimed at generating liquidity and NAV accretion.
The disposal to a consortium of other UK schemes was facilitated by online LP-led platform MeltX and received legal support from Willkie Farr & Gallagher and Hogan Lovells.
The LP-led deal was executed through the family office's investment arm M Eight, and represented nearly NIBC's entire private equity portfolio.
