A Colorado gasoline retailer is suing a broker who bought renewable fuel credits or RINs but refused to pay.

A RIN is the acronym for Renewable Identification Number, and were created by the Environmental Protection Agency to show compliance with the federal Renewable Fuel Standard. A RIN is assigned to every gallon of biofuel produced or imported into the United States.

Comprised of 38 digits, the RIN serves as a serial number which moves through the supply chain with the renewable fuel. A RIN can be separated from the renewable fuel and sold separately, offering flexibility for obligated parties under the RFS in meeting their Renewable Volume Obligation.

Western Convenience Stores Inc., based in Centennial, Colo., has filed a lawsuit against Matthew Thielen of Miami, Fla., with International Exchange Services LLC and Tradeixs, LLC seeking payment arising from the sale of about 2.72 million RINs last June at $290,569.

The complaint filed Nov. 6 by Western’s attorneys, Kenneth Bennington and Adam Aldrch, accuses Thielen and International Exchange of, among other things, breach of contract, fraud, theft and unjust enrichment and violation of Colorado consumer protection law.

Western is asking the United States District Court for Colorado to order the payment be made as well as seeking other damages.

The complaint says that Thielen approached Western on June 29 seeking RINs on behalf of International Exchange, a company registered in Delaware, but operates in Miami.

The following day, Western and International Exchange signed a purchase contract for the 2,722,782 RINs generated in 2008 and 2009. The RINs were transferred to International Exchange, with the understanding that payment would be made 10 days later.

However, International Exchange didn’t make the payment while Thielen, as the broker, then promising to make payment, but failed to do so.

In August, International Exchange made a payment of $75,000 but refused Western’s offers to settle the issue by either returning the RINs or making the rest of the payment.

The complaint alleges that Thielen may be the proprietor of both International Exchange and Tradeixs because they share a website, and Thielen is the listed owner of Tradeixs.