The rise of patent litigation is a well-known Silicon Valley saga, with tech firms buying up patents in droves to protect themselves against lawsuits — or, in the case of so-called “patent trolls,” small companies stockpiling patents just to sue others. All told, patent lawsuits have cost the economy a half-trillion dollars over the past two decades, according to a recent study.

The New England Journal of Medicine highlights an interesting twist on how similar issues are playing out in hospitals with copyrights. The fight isn’t even over a fancy piece of medical technology, but rather a simple mental health questionnaire.

Since the 1970s, doctors have used the Mini-Mental State Examination (MMSE), a 30-item screening test, as a first-line check on whether a patient has mental health issues. “For decades,” write doctors John Newman and Robin Feldman, the test “was widely distributed in textbooks, pocket guides, and Web sites and memorized by countless residents and medical students.”

That changed in 2000, when the test’s authors started taking steps to protect their copyright and began charging $1.23 for each use of the MMSE. Newman and Feldman don’t necessarily see this as problematic; the doctors who created the MMSE did, after all, develop a new screening test and do own the copyright. What Newman and Feldman find most troubling is a development this year: The MMSE creators used their copyright to block the creation of another, a 16-item screening that Harvard developed this year. The new diagnostic test, known as the “Sweet Sixteen,” was meant to be an open-access product. It was taken down this year in the midst of “an apparent copyright dispute.” More from Newman and Feldman:

For clinicians, the risk of infringement is real. Photocopying or downloading the MMSE probably constitutes infringement; those who publish the MMSE on a Web site or pocket card could incur more severe penalties for distribution. Even more chilling is the “takedown” of the Sweet 16, apparently under threat of legal action from PAR (although PAR has not commented publicly). Are the creators of any new cognitive test that includes orientation questions or requires a patient to recall three items subject to action by PAR? However disputable the legal niceties, few physicians or institutions would want to have to argue their case in court.

The battle over the mental health screening, these authors worry, may be a harbinger of more to come. “Many clinical tools we take for granted, such as the Katz Index of Independence in Activities of Daily Living, fall into the same ‘benign neglect’ copyright category as the MMSE did before 2000,” they note. And that could end up embroiling doctors in some of the battles that have become all too familiar in the tech landscape.