Perry, echoing the Federal Circuit decision, suggested that if a person can complete a process with a pencil and paper, that process shouldn't be patentable just because it is tied to a computer. But Roberts questioned that argument, suggesting that software can often make a process much simpler.
"What if you can do it without a computer but it's going to take 20 people 100 years?" he said.
Some critics of software patents were encouraged by justices' questions. Based on the questions, it appears likely that the court will invalidate the Alice patents, said Julie Samuels, executive director of Engine Advocacy, a trade group for tech startups.
"I'd be really surprised at the end of the day if these patents are left standing," she said after the hearing.
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