Italian prosecutors reportedly want four leading banks and asset management firm Nextra to stand trial over the collapse of food firm Parmalat.
Collapsed Parmalat has permission to re-float in Italy
The banks are Citigroup and Morgan Stanley of the US, Deutsche Bank of Germany and UBS of Switzerland, Reuters cited a judicial source as saying.
Prosecutors also want 13 executives from the firms to be tried.
Parmalat collapsed with debts of 14bn euros (£9.66bn; $17bn) but has gained permission to re-float in Italy.
The dairy firm's collapse in 2003 sent shockwaves through Italy where Parmalat was a household name and major employer.
The dairy firm misled borrowed money on the strength of invented assets before a spectacular collapse that left investors reeling.
In June, a Milan judge handed down jail sentences of up to two-and-a-half years to 11 people, mostly ex-Parmalat executives, who included the firm's former finance chief Fausto Tonna.
Prosecutors on Friday reportedly asked a Milan judge, Judge Cesare Tacconi, to send the five financial firms to trial for allegedly helping to mislead investors.
Hearings on the request to try the bankers are expected to take place in September.
Citigroup, which said in March it would countersue for damages after losing more than 500m euros on Parmalat transactions, denied that Citigroup or its employees acted improperly.
UBS said it did not consider its behaviour or that of its employees to be linked to market manipulation.
Morgan Stanley, Deutsche Bank and Nextra declined to comment on Friday's request.
Parmalat has not yet made any comment on the reported indictment requests.
Separately, Parmalat has filed a legal complaint against Standard & Poor's, the credit ratings agency, for giving it a credit-rating that failed to reflect the parlous state of its finances.