(updated with correction)
Partners Group closed its European Mezzanine fund at €553 million ($681 million), the largest mezzanine fund raised by the firm to date, confirmed spokesman Philip Sauer.
Fundraising began in the second half of 2008, and more than 99% of assets are from institutional investors, Mr. Sauer said in an e-mail response to questions. He would not disclose names of investors.
The fund has invested in more than a dozen companies, including German academic publisher Springer, U.K. retailer Pets at Home and Scandinavian health-care provider Ambea.
Partners manages 25 billion Swiss francs ($22.1 billion).