(Adds details on advisers, background)
MILAN, July 18 The banking foundation that used to be Banca Monte dei Paschi di Siena's top shareholder will seek damages from former members of its board and financial advisers in relation to the Italian bank's 2008 costly takeover of smaller rival Antonveneta, it said on Friday.
The 9 billion euro ($12.2 billion) deal badly stretched the finances of both Monte dei Paschi and the foundation which has since been forced to cut its over 50 percent stake in the lender to pay back debts.
In a statement, the foundation, which now has a 2.5 percent holding in the bank, said the advisers it planned to sue were those who released a fairness opinion on the price Monte Paschi paid to buy Antonveneta from Spanish bank Santander.
It did not name the advisers nor the former board members.
A source close to the matter said the advisers were Italy's Banca Leonardo and Credit Suisse.
Banca Leonardo could not be reached for comment and Credit Suisse declined to comment.
The acquisition pushed Monte dei Paschi's balance sheet to the limit just as the global financial crisis struck, precipitating an eventual state bailout of the 450-year-old bank.
The bank publicly acknowledged it did not carry out due diligence for its bid on Antonveneta, which Santander bought only a few months earlier in 2007 for 6.6 billion euros.
Monte dei Paschi raised almost 5 billion euros last month through a sale of new shares, allowing it to repay much of its state aid and avoid nationalisation. ($1 = 0.7398 Euros) (Reporting by Silvia Aloisi and Danilo Masoni, editing by Emilio Parodi and David Evans)