In a table-turning episode in the digital copyright wars, four teenagers are suing a business for allegedly trampling on their copyrights. Their product: homework.

The saga began last year when McLean High School in Virginia adopted a widely used antiplagiarism service called Turnitin. Under the system, students electronically submit essays to be stored and compared against millions of others in a massive database. Teachers can see if students are lifting work – a valuable tool given that research has found that 40 percent of undergraduate students admit to copying and pasting passages from websites.

But the setup rankled some students, who argued they shouldn't have to surrender their personal writing and persuasive essays – along with their names and e-mail addresses – to a computer bank in California.

"The suit is not about plagiarism; it's about the school forcing the students to turn their work over to a for-profit company," says Kevin Wade Sr., the father of a plaintiff. His son, a freshman in high school, whom Mr. Wade describes as a good student, "felt it was a privacy issue, and also [creates] an assumption of guilt."

Turnitin's creator, however, insists the gathered material goes no further than teachers and students, and is kept for the beneficial – and legal – purposes of stopping the scourge of plagiarism.

"This is really a social good to make sure that students who are not doing their own work are not rewarded for that," says John Barrie, president of the Oakland-based iParadigms, the company behind Turnitin.

Top copyright lawyers say both sides have compelling arguments. The Turnitin case highlights the mounting tensions between the social utility and economic value of searchable databases, and the ire they provoke over issues of privacy and profiting from another's work.

"There are a lot of businesses that depend on making [digital] copies in order to index, or make things searchable, or create filters, or [perform] matching. All of these kinds of things today are valuable and in high demand," says Fred von Lohmann, a lawyer with the Electronic Frontier Foundation in San Francisco. "You'll see a lot more cases involving indexing copy."

7,000 schools use Turnitin

Some 7,000 schools and other institutions now use Turnitin, including the California State University system, the University of Florida, and Georgetown University. The pricing has proved attractive, at less than a dollar per student for an entire year.

Students submit their papers – some 100,000 a day – through a Web form, and Turnitin calculates a "similarity index." This score is a percentage of the paper that closely matches the wording found in other sources, either online or in the database.

About 30 percent of papers received by Turnitin are found to be more than a quarter unoriginal, says Dr. Barrie. Half of that copied work comes from online sources. "Students are using the Internet like an 8-billion-page, searchable, cut-and-pasteable encyclopedia," he says.

Limited access to content

When matches are found to an existing student paper, the teacher can ask the other student's teacher to see the earlier work in full.

Critics of Turnitin such as Mr. Wade point out that this process doesn't seek the permission of the authors – the students. They also worry where the work could wind up in the longterm since iParadigms reserves the right to sell the database and its contents.

These "republishing" avenues are at the heart of the lawsuit filed late last month, which seeks $150,000 – the legally stipulated penalty – per paper registered by the four students.

"There is no way on God's green earth that we're ever going to turn a student's paper over to anybody except that student and their instructor until the end of time," says Barrie.

There still are those exceptions, which critics point out. But Barrie says, when a student's teacher decides to pass a paper to another teacher, no name is attached. And, in the event iParadigms is bought out, institutions can exercise their ability to cancel service and get their papers expunged.

That still doesn't give students any control, however, and parents say their children are facing coercion. Wade says his son was told by a teacher to use Turnitin and accept the company's terms of use, or face getting an F.

Lawyers weigh in on students' case

Experts in copyright law say that the age of the students helps their case, as minors aren't held as tightly to agreements that sign over rights.

Several top intellectual property lawyers say that if the case goes to court it could come down to a "fair use" judgment call. Fair use carves out exceptions to copyright to allow for a freer flow of information.

"It's been a confused and ambiguous issue long before the Internet came along," says Andrew Beckerman-Rodau, a professor at Suffolk University Law School in Boston. "The Internet just has made more cases come up because previously a lot of works that had no real value suddenly have value because you can distribute them on the Internet."

Demand is almost certainly nil for a teenager's ruminations on Moby Dick. At the university level, the issue is more pressing. Michael Smit, a critic of Turnitin, says he wrote papers with marketable ideas during his time as a computer science graduate student at Dalhousie University in Halifax, Nova Scotia a school that uses the system.

"I have applied for patents. I came up with unique ideas during my university days. And I'm not a big fan of sending them to a company forever to store," he says.

However, databases like Turnitin, as well as Google's book-scanning project and search engines for images, also create a value of their own.

In some ways, the modern Web has been built upon such services where material is gathered and reused in ways that the original creators never had in mind, says Jonathan Zittrain, professor of Internet governance and regulation at Oxford University.

"One does not have to be a kind of copyright anarchist," he says, to appreciate the thicket that can arise when at any moment that somebody benefits from the action of another [online], the person can say, uh-uh-uh, pay me."