To cut costs for books, Matt Panopio bought his thermodynamics textbook from an international seller through eBay for about $50 cheaper than the cover price.

Shortly after receiving his book in the mail, the second-year civil engineering student realized the international version of the book was different than its American counterpart.

“The American version has tables and graphs at the end of the book that you need for class, which is probably the most important part of the textbook,” he said. The international version does not have that feature.

The nation’s highest court is now evaluating whether textbooks produced abroad, like the one Panopio received, can be sold in the United States at lower prices.

Last month, the Supreme Court announced it will rule on a case debating the issue. The case, John Wiley & Sons, Inc. v. Supap Kirtsaeng, dates back to 2008, when publishing company Wiley & Sons sued Kirtsaeng for selling textbooks bought from abroad within the United States through a markup company. Kirtsaeng was a graduate student at the University of Southern California at the time.

The suit brings into question the Copyright Act of 1976, which outlines rules for copyrighted materials, including textbooks. One of the sections of the act states that the owner of a copyright, Wiley in this case, has the exclusive right to distribute copyrighted works to the public.

But another section within the act, known as the first sale law, allows purchasers who have lawfully acquired the work to dispose of it as they wish, said Peter S. Menell, a professor of law at UC Berkeley.

The main question of this new case is whether a lawful purchase abroad comes with the same right to resell, he said.

Kirtsaeng contends that he was justified in reselling the materials under the first sale law, while the publisher makes the argument that it only has the authority to distribute copyrighted materials, according to court documents.

A district court sided with the publisher in 2009, ordering Kirtsaeng to pay the publisher $600,000 for violating the company’s copyrights.

Kirtsaeng’s attorney, Sam P. Israel, said they are now looking for the Supreme Court to reverse the lower court’s decision, citing the first sale law.

Before the court rules on the case, students should be cautious about reselling imported books, Menell said.

Used books sold on sites like Amazon or ebay might or might not be are most legitimate copies. If the copy being sold is imported without authorization of the publisher, the seller runs afoul of copyright law, he said.