Mr Cosby did not personally make a bid for the television network but his agent, Norman Brokaw, approached a top executive at NBC last week, the newspaper New York Newsday reported.
Mr Brokaw, chairman of the William Morris Agency, 'communicated Mr Cosby's interest and desire' to buy NBC, Mr Brokaw's son David, a Cosby spokesman, said.
Mr Cosby told the network through an intermediary that he would not be the only person involved in a formal bid, Newsday said.
'It's for real. It is serious. It's not a rumour,' David Brokaw said.
'He's obviously got some ideas about quality TV.'
Mr Cosby has in the past criticised the portrayal of black people on television.
The 55-year-old actor-comedian is worth more than dollars 300m by Forbes magazine's estimate. GE, which paid dollars 6.4bn ( pounds 4.06bn) when it acquired NBC in 1986, is reported to be seeking dollars 4bn for it, but analysts have said it is worth much less.
Among others who have reportedly expressed interest in the network are the former Fox chairman Barry Diller and Paramount Communications, headed by the former NBC entertainment president Brandon Tartikoff.
Mr Cosby has been associated with NBC since 1965. The network carried his hit The Cosby Show from 1984 until last spring.
Other US newspaper reports said that Mr Cosby had pulled away from the deal when he failed to find other investors.
NBC yesterday declined to comment on the newspaper speculation.Reuse content