Anonymous sources have claimed that HSBC Holdings staff are alleged to have conspired with Vaibhav Dahake to cover up bank accounts in India from the attentions of the Internal Revenue Service (IRS).
The entrepreneur was indicted in an American court earlier this week and was said to have collaborated with "one of the largest international banks in the world", although HSBC itself was not specifically named as the party concerned.
Spokeswoman Juanita Gutierrez strenuously denied the firm was guilty of any wrongdoing and insisted it had rigorous internal policies intended to weed out members of staff responsible for breaching tax regulations.
"HSBC does not condone tax evasion and fully supports the US efforts to promote appropriate payments of taxes by US taxpayers," she said in a statement. "We investigate all allegations of employee misconduct vigorously."
Mr Dahake's legal representative Lawrence Horn said the indictment was "regrettable" and insisted that his client was "cloaked with the presumption of innocence" until proven guilty in a court of law.
The businessman is accused of falsifying tax returns which failed to declare his ownership of accounts in both his native India and the British Virgin Islands. According to court filings, his bank encouraged him to open Indian accounts to take advantage of high interest rates.
In addition, the unnamed financial institution set up an American division dedicated to encouraging US citizens of Indian origin to open accounts in the Asian country, marketing them as providing high-interest returns.
Earlier this month, Indian police confirmed they had no plans to press charges against top Citigroup executives including chief executive Vikram Pandit, after several bosses were named in a complaint over alleged fraud at a New Delhi branch.
By Tony Aynsley