July 18, 2013 - A software glitch saw US bank Citi fail to redact the personal information of nearly 150,000 people in bankruptcy filings, according to court documents unsealed this week.

Between 2007 and 2011 various Citi subsidiaries filed proofs of claim in thousands of consumer bankruptcy cases seeking payment of amounts alleged to be owed by debtors.

But in April 2011, the bank says that it discovered that personal information - including social security numbers and dates of birth - that should have been redacted from these claims under bankruptcy court rules, was not.

A Citi spokeswoman told Dow Jones that limitations in the redaction technology was to blame for the issue which meant that anyone with the technical know-how could access the personal information online via the electronic court records. The bank says it has "no reason to believe" that any data was misused.

In a settlement reached last year and unsealed this week, Citi agreed to go back and redact the proofs of claims and write to the affected people, offering a year of free credit monitoring. Meanwhile, an independent auditor is reviewing the bank's redaction and replacement process.