Sullivan & Cromwell, a storied Wall Street firm that took on its first debtor side bankruptcy role nearly six years ago, is now representing offshore drillship operator Pacific Drilling SA in a Chapter 11 case filed by the company earlier this month.

Luxembourg-based Pacific Drilling and nearly two dozen affiliates filed for bankruptcy on Nov. 12 in Manhattan as part of an effort to restructure some $3 billion in debt. The company, the latest drilling business to run into financial troubles amid low oil prices, listed in court records assets and liabilities of between $1 billion and $10 billion.