This article describes how a Goldman Sachs contractor accidentally sent an email containing confidential client information to a random Gmail account, and how the bank sued Google to un-send the email and prevent a potential data breach. The email was meant for a gs.com account, but the contractor added an extra letter and sent it to a gmail.com account instead.
The article also explains that Google refused to cooperate with Goldman Sachs unless it obtained a court order, and that the bank filed an emergency injunction in a New York state court to block the Gmail account owner from accessing the email. The article cites a Goldman Sachs spokesperson who said the bank had no evidence that the email had been accessed or misused, and that it was working with Google to resolve the issue.