UPDATE 1-NYMEX prices secondary share offering

(Adds details, closing share price)

NEW YORK, March 21 (Reuters) - NYMEX Holdings Inc. NMX.N, which owns the world's largest physical commodities exchange, said on Wednesday it has priced its secondary offering of 7 million shares at $136.50 per share.

The parent company of the New York Mercantile Exchange said the shares are being offered by NYMEX stockholders who elected to sell shares.

The offering, priced at a slight discount to Wednesday's closing price of $136.70, is worth $955.5 million.

NYMEX will not receive any of the proceeds from the offering, the company said in a statement.

J.P. Morgan Securities Inc., Banc of America Securities LLC and Merrill Lynch, Pierce, Fenner & Smith Inc. are acting as joint book-running managers for the offering.

The underwriters have an option to purchase up to an additional 1.05 million shares to cover possible over-allotments.

The offering is expected to close on March 27, subject to customary closing conditions.