UniCredit SpA has lent about €600 million ($655 million) to companies that are part of Austrian tycoon Rene Benko’s Signa group of companies, according to people familiar with the matter.

The loans, mainly through its Bank Austria unit, are to individual companies within the conglomerate and all are collateralized, the people said, asking not to be identified discussing private information. The Italian lender doesn’t have any exposure to the real estate group’s ultimate parent, Signa Holding, they said.

A spokesperson for UniCredit declined to comment.

UniCredit is part of a long list of banks that have extended credit to Signa, which is turning into one of the most prominent casualties of Europe’s property crisis after the holding company filed for insolvency on Wednesday. Swiss wealth manager Julius Baer Group Ltd. has 606 million Swiss francs ($692 million) in loans to Signa, an exposure that’s now prompted a review of how it lends money to its richest clients.

Signa is comprised of hundreds of individual legal entities. The two main operating units — Signa Prime and Signa Development — had more than €13 billion in financial liabilities at the end of last year. Lenders to Signa face varying degrees of risk based on which entity they have loaned money to and what kind of collateral, if any, those entities have pledged.

--With assistance from Sonia Sirletti, Stephan Kahl and Marton Eder.