"AARP believes it is in the interest of those fifty and older, and indeed the public at large, to hasten the entry of generic prescription drugs to the marketplace," said Ken Zeller, senior attorney with the AARP Foundation Litigation. "Pay-for-delay agreements such as those at issue in this case frustrate that public interest."

 The American Medical Association, the giant doctors' group, believes pay-for-delay agreements undermine the balance between spurring innovation through patents and fostering competition through generics, AMA President Dr. Jeremy A., Lazarus said. "Pay for delay must stop to ensure the most cost-effective treatment options are available to patients."

 Drugstores also believe pay-for-delay deals "pose considerable harm to patients because they postpone the availability of generic drugs which limits patient access to generic medications," said Chrissy Kopple of the National Association of Chain Drug Stores.

 Eight justices will decide this case later this year. Justice Samuel Alito did not take part in considering whether to take this case and is not expected to take part in arguments.