The academic technology company Blackboard stirred up criticism earlier this year when it obtained a patent that some claimed gave it a monopoly on the blanket concept of e-learning.
The Washington-based firm didn't make any new friends when it reportedly turned around and sued rival Desire2Learn for alleged infringement the day after it received the privilege.
Now a free and open software group has lodged a formal challenge against the intellectual property rights granted to Blackboard.
It says its request presents documents that predate the patent and "describe everything in it." In order for an invention to receive patent protection, it's supposed to be novel, useful and non-obvious.
The announcement of the re-examination request comes just two days after the U.S. Supreme Court heard arguments about what makes an invention too "obvious" to warrant protection. Several justices appeared to be leaning toward changes in the law that may render it more difficult to obtain patents in the future.