A group of investors who lost hundreds of millions of euro in the collapse of Banco Espírito Santo has filed a lawsuit challenging the European Commission’s decision to approve Portugal’s bailout of the bank.

The lawsuit, filed on Friday at the EU's Court of Justice in Luxembourg, could cast doubt over Portugal's plan to sell Novo Banco, the main entity to emerge from the wreckage of BES.

The investors, including Dan Loeb’s hedge fund Third Point and Brazilian investment bank BTG Pactual, have already filed a legal challenge against the Portuguese central bank over its restructuring of the distressed lender.

The €4.9 billion rescue of BES protected taxpayers and senior creditors by leaving them in a “good bank”, now called Novo Banco, but left shareholders and subordinated creditors in a “bad bank” holding only toxic assets. In their application for annulment of the state aid approval the investors argue the EU “committed numerous manifest errors of law”. –(c) 2014 The Financial Times Limited