Alternatively, the court could lower the standard of proof only in situations where an infringer presents new evidence that the patent office has not already considered, as Microsoft has done.

A third option is to leave the current required standard of proof unchanged.

If the court does lower the standard, it would become easier to invalidate patents, Columbia said. "Over time, if the burden of proof is lowered to prove invalidity, you'll find more cases where patents are found to be invalid," she said.

She and others describe other potential consequences

"There is already enormous pressure for patent attorneys to file every piece of prior art they can think of. If you create this double standard, where art that's not before the patent office somehow weakens the patent, there's even more pressure to [file every piece of prior art]," she said. "We already have a situation where the examiners are fairly overwhelmed with the volume of work. I think we're going to make it worse" if the Supreme Court sides with Microsoft.