The offer is said to be less than the current four-year figure and has been reported at $1.4 billion.
An NBC spokesman declined to comment during negotiations.
AOL cable connection
AOL Time Warner's Turner Broadcasting System is believed to have reached a deal in principle to re-up as a cable carrier of the games, but that deal is not expected to close until the NBA decides how to proceed with NBC.
That's because the Walt Disney Co. is also in the mix negotiating for its ABC and ESPN outlets, and if the NBA decides to balk at NBC's offer, it could make a deal with Disney making ESPN a second national NBA cable outlet to carry regular season and some playoff games while the NBA finals would be on ABC.
A Turner spokesman declined to comment. An ESPN spokesman said Disney is still involved in discussions.
Rebranding of CNN/SI
The Turner deal is expected to also include the rebranding of CNN/SI as a third all-sports channel to compete with ESPN and Fox Sports Net. The NBA would own 50%.
In past years, incumbents NBC and Turner would likely have quickly re-upped during their exclusive negotiating periods, but a weak ad climate and an apparent hesitancy among top corporate executives to write large checks for sports rights fees has drawn the process out.