The U.S. Department of Justice is siding with Argentina in a legal case of $18 billion relating to the 2012 nationalization of Argentinian oil company YPF. In 2012, the Argentine government took control of the country’s largest oil and gas company, YPF S.A. The legal fight stems from Argentina’s 2012 expropriation of YPF shares from Spain’s Repsol without extending a mandatory tender offer to YPF’s then minority shareholders—Petersen Energia and Eton Park Capital. After the renationalization…