The conglomerate led by Asia's richest man, the Indian billionaire Gautam Adani, said last week's Hindenburg report was intended to enable the U.S.-based short seller to book gains, without citing evidence.
This has been overshadowed by the Hindenburg report, which flagged concerns about high debt levels and the use of tax havens.
Hindenburg did not immediately respond to a request for comment on the Adani response on Sunday.
The report also said five of seven key listed Adani companies have reported current ratios - a measure of liquid assets minus near-term liabilities - of below 1.
It also said key listed Adani companies had "substantial debt" which has put the entire group on a "precarious financial footing" and that shares in seven Adani listed companies have an 85% downside on a fundamental basis due to what it called "sky-high valuations".