Brazil Bank Collapse Spells Turmoil for Firms Holding Its Debt

A handful of Brazilian companies are disclosing exposure to Banco Master SA following the liquidation of the troubled lender and the arrest of its chief executive amid a sweeping corruption probe.

Health-care provider Oncoclinicas reported holding 433 million reais ($81.1 million) in Master time deposits, known locally as CDBs. It had provisioned losses of about half that amount in its latest earnings report, and said it will take “appropriate measures” to cover the rest — which represents a little less than half of the company’s cash position at the end of the third quarter.

Oncoclinicas, which has seen its shares ...