A judge has found key parts of Michigan’s newborn blood-testing program unconstitutional after four parents raised concerns about leftover samples being used long after screening for rare diseases.

While the lawsuit is not a class action, the decision this week will likely impact how the state maintains millions of dried blood spots and makes them available for outside research.

Michigan hospitals normally prick the heels of newborns to draw blood to check for diseases. This is a routine practice for most hospitals across the U.S. Leftover blood spots are then sent to the Michigan Neonatal Biobank in Detroit where scientists can pay a fee to use them for various research projects.

Since 2010, Michigan must receive consent from parents to use the blood spots for outside research. However, attorney Phil Ellison says that the program still violated constitutional protections against searches and seizers and may be misunderstood by parents signing the form soon after childbirth.

Ellison argues that the form is vague and does not provide parents with enough information about the research.

Federal Judge Thomas Ludington ruled in favor of the parents on over a dozen issues.