(Reuters) -A U.S. judge granted preliminary approval on Friday to a $177 million settlement that resolves data security lawsuits against AT&T ( T ) over breaches that exposed personal information belonging to tens of millions of the telecom giant's customers.

U.S. District Judge Ada Brown in the federal court in Dallas, Texas, said in a ruling that the class-action settlement was fair and reasonable.

The deal resolves claims over data breaches that AT&T ( T ) announced in May and July last year.