Saying it understands that shareholders rights plans are looked upon unfavorably by shareholders and institutional investors, TETRA Technologies (NYSE:TTI) allowed its poison pill plan to expire last night at 5:00 p.m., Houston, TX time, by approving an amendment accelerating the expiration date of the preferred stock purchase rights from Nov. 6, 2018 to March 13.

"In light of the general disfavor of 'poison pill' plans by institutional investors and stockholder groups," TETRA's president and CEO Stuart M. Brightman said in a statement, "our board of directors has determined that the termination of the rights plan will demonstrate our goal of maintaining sound corporate governance policies and procedures throughout our company."

According to data on Yahoo! Finance, institutional investors and mutual funds own 86% of TETRA Technologies' stock, and 89% of its float. Insiders hold just 3%. 

TETRA is a geographically diversified oil and gas services company. It adopted the stockholders' rights plan on Oct. 27, 1998, as a means of assuring all of its stockholders receive fair and equal treatment in the event of a proposed takeover.

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