A U.S. federal judge confirmed on Monday that a $3.7 billion bid from Red Tree Investments, a subsidiary of Contrarian Funds, will serve as the starting point in the auction for Citgo Petroleum, the U.S. subsidiary of Venezuela's state-owned oil company. This auction is aimed at liquidating assets to satisfy creditors and bondholders, triggering a complex legal and financial contest among 16 creditors vying for a share of Citgo's estimated value.