Centennial Communications

AT&T announced a $944 million buyout of Centennial Communications Corp. on November 11, 2008. The acquisition was subject to regulatory approval, the approval of Centennial’s stockholders and other customary closing conditions. Welsh, Carson, Anderson & Stowe, Centennial’s largest stockholder, agreed to vote in support of the transaction. AT&T hoped to obtain approvals by the end of the second quarter of 2009. In an attempt to quell regulators, on May 9, 2009, AT&T entered an agreement with Verizon Wireless to sell off certain existing Centennial service areas in the states of Louisiana and Mississippi for $240 million pending the successful merger of AT&T and Centennial.

On July 8, 2009, AT&T announced a delay in the acquisition of Centennial, being postponed to by the end of the third quarter of 2009. The delay was announced shortly after the U.S. Department of Justice began an investigation on AT&T and Verizon Communications for anti-competitive behavior due to both carriers' massive growth.

On November 6, 2009, the FCC gave final approval to AT&T's buyout of Centennial Communications. AT&T divested five markets in Louisiana and Mississippi to Verizon Wireless. Three additional markets were divested to an unknown buyer. AT&T temporarily continued to operate Centennial's CDMA networks in Puerto Rico and the U.S. Virgin Islands, rather than immediately move all customers to GSM/UMTS. On July 18, 2010, AT&T absorbed Centennial in the Caribbean and the Centennial brand became AT&T.

As of 2020, AT&T sold its wireless networks in Puerto Rico and the U.S. Virgin Islands to Liberty Puerto Rico with the sale completed in 2020.