Investor group Lloyds Action Now (LAN) is representing 1,500 US shareholders who claim they were misled over its acquisition of its struggling rival in 2008.
LAN, one of a number of shareholder action groups disputing Lloyds' takeover, argues shareholders were not given full details of HBOS's financial woes and will launch a class action against the bank.
The group, which is also pursuing a UK legal case against Lloyds, said a claim would be filed in the US courts "within months". It has also written claim letters to former Lloyds chairman Sir Victor Blank and retiring chief executive Eric Daniels.
LAN argues lack of details in the Lloyds takeover prospectus of a 25.4bn emergency Bank of England loan to HBOS meant that vital information was withheld. It claims 800,000 Lloyds shareholders have lost 2bn between them and have had dividend payments suspended.
A Lloyds spokeswoman said the group believed the disclosures were thoroughly, clearly and appropriately made to shareholders and it did not consider there to be any legal basis for a claim against Sir Victor and Mr Daniels.
EQUITABLE LOSERS SET FOR BIGGER PAYOUT
Victims of the near-collapse of insurers Equitable Life look set for a more generous payout than expected, it has emerged.
Chancellor George Osborne will use Wednesday's Comprehensive Spending Review to announce compensation amounting to around 1.5bn to policyholders who lost pensions and savings, according to the Daily Mail.
The sum is more than three times the maximum 400m-500m payment recommended by former judge Sir John Chadwick, who was appointed by the last government to determine compensation.
More than one million policyholders lost out when Equitable came close to going bust in 2000. Many have died waiting for compensation and it is understood that their relatives will benefit from the payout.
Treasury sources declined to comment on the report.