An Illinois judge has approved a preliminary $21 million class action settlement brought by Big Sky Excavating Company against AT&T for allegedly issuing improper refunds to businesses with multiple lines. Big Sky led a class of small businesses who claimed they were not properly refunded for AT&T overcharges. State law mandated AT&T to pay out $90 million in refunds to affected business customers in 2001.

Big Sky and other small businesses never received their refund, prompting Big Sky to file a class action suit in 2003. According to the Madison Record, a 2009 judgment found that AT&T had improperly paid out refunds to recipients who weren’t supposed to receive them.

The final class action settlement approval hearing is scheduled for July 12, 2010. Class members have until June 23 to opt out.