The American Institutes for Research is going back to court to fight the granting of a potentially enormous award for common-core testing work to Pearson—in a legal effort designed to limit the length of the contract and correct what it sees as an unfair process.

After a recent defeat, the Washington-based testing organization is filing an appeal of the contract, which was given by the states belonging to the PARCC testing consortium to Pearson, in state court in New Mexico. Officials in New Mexico oversaw the original, disputed bidding process, though the contract has implications far beyond that state.

In its legal appeal—you can access it here— the AIR seeks to slice the contract award down to one year and cancel the years after that.

In a statement, AIR officials say they interpret the contract as awarding Pearson work for up to eight years—”effectively committing a billion dollars in a sole-source contract.”

Filed in the First Judicial District Court in Santa Fe, N.M., the lawsuit seeks to have the state conduct another, separate bidding process for the later contract years. The AIR also asks the court to order the state to create a new procurement for years two of the contract and beyond—or, that the court declare that the existing contract is only valid between Pearson and New Mexico’s department of education, and that the state “shall not permit any third party, including any other state or agency thereof, to join or participate in the procurement.”

The AIR has argued that the request for proposals put forward for common-core testing work on behalf of states belonging to the Partnership for Assessment of Readiness for College and Careers was skewed in favor of Pearson. A central allegation was that the contract improperly bundled testing work that Pearson had already won through a separate award with PARCC with new testing work—which unfairly gave the company the upper hand.

Ultimately, Pearson was the only company to submit a bid for the work, and it was awarded the contract this spring. Officials from the AIR say they would have submitted a bid if they had thought the process was fair.

When the AIR filed its initial protest, New Mexico’s state purchasing agent rejected it, saying it had not been filed in time. A state judge disagreed, ordering the purchasing agent to review the protest on its merits. Then, earlier this month, the state purchasing agent, Lawrence O. Maxwell, officially denied the AIR’s argument, saying state officials had made a convincing case that the RFP was carried out in a proper way.

A spokesman for PARCC, David Connerty-Marin, said the organization’s member states were moving forward, regardless of the lawsuit.

“The PARCC states have been confident from the start that New Mexico conducted a fair and open process,” Connerty-Marin told Education Week. “We’re focused on implementing high-quality work.”

The lawsuit, he said, ultimately “puts AIR’s corporate interests” above those of students.

The AIR had sought to broker a deal with PARCC officials so that it would not have to go to court, but those efforts did not succeed, said Jon Cohen, the president of the AIR’s assessment division.

The AIR is not asking the court for an injunction, or for a cancellation of the overall contract—only that the initial length of the contract be limited, Cohen said. The limited nature of the appeal is intentional, he added, because the AIR does not want to derail PARCC’s overall work from going forward.

“We’d like see PARCC succeed,” Cohen said. “That was our hope and goal.”

Check back on Marketplace K-12 for more details as they roll in.

This post has been updated with additional details from the lawsuit.