Quest Diagnostics

(DGX) - Get Report

said its board approved a 2-for-1 stock split.

The additional shares will be distributed May 31 to shareholders of record May 16. The company, which does clinical testing, has about 47 million common shares outstanding. The company has the authorization to issue 100 million shares, but stockholders will be asked to increase that authorization to 300 million shares at a meeting in early May.

Quest Diagnostics, which is based in Teterboro, N.J., closed down $2.39, or 2.4%, to $99 on the

New York Stock Exchange

.