Waterland Private Equity Investment's sale of Amsterdam-based Intertrust has attracted interest from Blackstone, Carlyle and Cinven.
According to Reuters, Bridgepoint, CVC Capital Partners and 3i have also been mulling over a potential deal.
ING is managing the auction, which will accept first-round bids from 12 September. Debt packages ranging between €400m and €500m are being prepared by banks ahead of the deal if the transaction is won by a private equity bidder.
Waterland acquired Intertrust in September 2009, after the tax administration subsidiary of Fortis attracted first-round bids from Permira, CVC and General Atlantic.
Waterland was believed to have paid around €250m for the business, well below the €350m asking price. The sale was pushed through by the Dutch government because of Intertrust's focus on helping companies and wealthy individuals pay as little tax as possible, often using offshore vehicles. As governments continued to clamp down on the use of tax havens, the first-round bidders quickly dropped out of the process.