The DOT decided that licenses would be allotted on a "first-come-first-serve" basis at low prices that were current way back in 2001, against the advice of the local telecom regulator, Telecom Regulatory Authority of India (TRAI), CBI said.

The DOT’s decision to put a cap on the number of licensees per service area, and a decision to stop accepting new applications even before the last date fixed has also come in for criticism.

The CBI said that by putting a cap on the number of licenses, there had been a criminal conspiracy between certain officials of the DOT and some private companies and individuals to award licenses to select companies.

The CBI was criticized severely by India’s Supreme Court last month for the delay in completing the investigations.

A number of the licensees said to have benefited from the allegedly irregular allotment of licenses and spectrum later went on to sell stakes in their services companies to foreign investors like Telenor, at prices far higher than the amount paid by the licensees for the spectrum, according to India's opposition parties.