What happens to unclaimed rebates when customers don’t, well, claim them? In Illinois, the state treasurer’s office says Sprint owes customers $2.7 million in rebates from 2003 to 2005 that were never claimed, accusing another company of keeping those funds for itself.

The Illinois treasurer’s office filed a lawsuit in Cook County Circuit Court against Sprint, claiming the phone carrier owes nearly 32,000 residents a hefty chunk of change for the unclaimed rebates, reports the Chicago Tribune.

The lawsuit also names Young America, a rebate clearinghouse, for allegedly lining its own pockets with rebate proceeds from Sprint promotions offered more than a decade ago.

Young America, which is now called YA, processes rebate rewards, contests, and other promotions. Part of its deal with Sprint meant it would receive the funds needed to pay out the rebate checks, but was allowed to hang onto those unwashed rebates, known as “slippage.”

But the lawsuit claims those uncashed checks sitting in Young America’s pockets violate the Illinois Uniform Disposition of Unclaimed Property Act, which says that funds or other property that goes unclaimed for more than five years must be handed over to the treasurer’s office. There it will sit, for time eternal… or until someone finally claims it.

“It is frustrating and wrong when these large companies with deep pockets and corporate attorneys break their promises, keep money that is not theirs, and dare people to file a lawsuit,” Illinois Treasurer Michael Frerichs said in a statement Tuesday.

Sprint denies the lawsuit’s allegations.

“This lawsuit is not about rebates that were withheld, but about rebate checks that were sent, but not cashed. We do not believe the claims against Sprint have merit, and we will continue to seek a fair resolution in our settlement discussions with Illinois,” a spokesperson for the carrier told the Chicago Tribune.

Illinois isn’t the first state going to bat against Sprint and Young America over unclaimed rebates: in 2010, 36 states reached a $22 million settlement for Sprint rebates owed from 1999 to 2002, the Chicago Tribune notes.

Sprint rejected settlement offers with Illinois, although it had reached similar agreements with other states, which is why officials say they filed the lawsuit.

Illinois sues Sprint over $2.7M in unclaimed rebates owed to customers [Chicago Tribune]

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