Engineering and construction major Larsen an Toubro (L&T) and the telecom gear maker Spice Corporation are among the seven players shortlisted for Satyam bidding, even as the CBI probing into the the accounting fraud at the IT major said it has enough reason to believe that the scam involves a much bigger amount - close to Rs10,000 crore - against the 7,000 crore that the IT company's founder Ramalinga Raju owned up.

The list of possible bidders shortlisted for sale of a 51 per cent stake in the fraud-hit IT firm also includes three private equity funds, sources said.

Earlier,  iGate, the US-based IT company that has opted out of the bidding process to acquire majority stake in Satyam Computer Services, had said that it took the decision keeping in mind the ''totality of concerns''.

iGate itself did not attribute any reasons for its withdrawal from the bidding process. ''There was no one particular reason, it is the totality of concerns like sliding revenues, unknown margins and large liabilities that made us pull out of the race,'' Phaneesh Murthy, president and chief executive of iGate said.

Satyam, which has been looking for a buyer to help revive it after its founder B Ramalinga Raju revealed in January that he overstated the company's profits over several years, is likely to send letters to shortlisted bidders soon.

Reports quoting CBI sources said on Monday that the agency has retrieved over 7,000 fake invoices and forged documents showing fixed deposits and bank balances and their evaluation shows that the size of the scam is over Rs 9,600 crore.

The report also said CBI has unearthed about 7,000 fake invoices that were fed into the company's books to generate virtual income to the tune of Rs4,500 crore.

According to the CBI, the accused, including founder chairman Ramalinga Raju, his brother and two other officials of  the audit firm PriceWaterhouse Coopers, also have given false and fabricated statements about high capital of the company. These inflated figures were also reflected in the balance sheet in the form of audit reports which helped the company to cheat the public who were purchasing its shares.

The accused forged documents and created fake fixed deposit receipts to the tune of Rs3,300 crore.  They also allegedly manipulated bank guarantees to show the balance in bank accounts as Rs1,800 crore.

Forged bank documents with Satyam also showed the existence of the cash balance in five banks, including ICICI Bank, HSBC, Citibank and BNP Paribas but the banks clarified that they do not have any cash balance in the name of the firm, CBI alleged.