Chart Industries Inc. has announced shareholders that own nearly half the company's shares have begun a secondary offering of 12.6m shares.

The maker of cryogenic equiment said sellers include FR X Chart Holdings LLC, an investment fund affiliated with First Reserve Corp., which is offering its entire stake of nearly 12.4m shares. FR X is the largest shareholder of Chart, which has about 25.8m shares outstanding.

Executive officers, including CEO Sam Thomas are also selling stock, believed to be around 140,000 shares, while certain other employees are selling 96,434 shares.

The company said it won't receive proceeds from the stock sale. Chart will grant the underwriters the option to buy up to nearly 1.9m shares to cover overallotments. If the overallotment option is exercised, Chart said it will use the proceeds for general corporate purposes, including debt reduction.