More than 100 individuals in Mumbai, including a few corporate biggies, have received notices from the Income-Tax Department this month for holding undisclosed bank accounts with HSBC Geneva.

They are among the 700 Swiss bank account holders whose names figure in the list shared by the French authorities with the Indian government a few months ago. The French had obtained the information from a former HSBC employee.

The tax department is in a hurry to meet the December 31 deadline set by the Central Board of Direct Taxes for sending notices to these individuals.

"A few prominent names in Mumbai's corporate world are in the list," a senior incometax official told ET. He said some of them have voluntarily disclosed their numbered accounts following which they were served notices under Section 148 of the Income Tax Act.

It's a procedure the taxman follows to regularise an assessment after collecting the unpaid tax amount together with the interest. In some cases, the department also uses its discretion to slap penalties. Members belonging to a leading industrial family have disclosed their HSBC Geneva accounts.

"One of them is based in Mumbai while the other family member is based down South. The latter is a beneficiary of a trust that holds Rs 300 crore in its HSBC Geneva account.

The amount disclosed by the person in Mumbai is about Rs 50 crore," said a source in the tax department. He confirmed that subsequently these individuals have revised their tax returns as allowed under Section 148.

Of the 700 in the list, close to 200 account holders of HSBC Geneva are from Mumbai. The tax department is expected to serve notices to more people once it surveys their offices and in a few cases residences.

"Not all who have received notices have replied," said a tax official. According to him, the department will soon have to deal with more such lists of Swiss bank account holders.