Food and dairy company Parmalat said Thursday it has filed a lawsuit seeking $6.6 billion in damages from the Swiss regional bank Graubuendner Kantonalbank, another in a series of lawsuits against banks and auditors it claims helped lead the company to collapse.

Parmalat alleges complicity between GKB and former bank officers Nino Giuralarocca with Bank of America and former Parmalat Group managers in arranging and managing complex financial transactions “that allowed the former Parmalat Group artificially to continue trading from at least 2001.”