On Tuesday morning, the CRISPR patent dispute reaches a much-awaited milestone: the case’s first and only oral arguments, slated to last less than an hour for a patent potentially worth billions of dollars. The hearing is open to the public, and it’s sure to attract the attendance of dozens of lawyers, company executives (Novartis has confirmed it’ll be represented), publicists, reporters, and even some genome-editing groupies.

The nasty dispute pits the University of California against the Broad Institute of Harvard and MIT for rights to key patents on CRISPR genome-editing. Since April 2014, the Broad has received 13 CRISPR patents, based on work led by its bioengineer Feng Zhang, but UC believes it deserves some of the most foundational ones, reflecting earlier work by its biochemist Jennifer Doudna and her collaborator Emmanuelle Charpentier.

The hearing, which begins at 10 a.m. EST in Alexandria, Va., offers each side just 20 minutes — and that includes questions from the three judges of the Patent Trial and Appeal Board, part of the US Patent and Trademark Office. “I have rarely known a judge not to interrupt,” said Robin Feldman, professor of law and director of the Institute for Innovation Law at UC Hastings College of the Law. So the lawyers need to be nimble, pivoting quickly from their prepared arguments (with slides) to the judges’ questions and back again.

The judges sit behind monitors, allowing them to call up any of the hundreds of exhibits and other documents that the lawyers refer to. Judges tend to be poker-faced, said one lawyer with PTO experience, and rarely give clues about what they’re thinking or what arguments — including those already submitted in writing — are commanding their attention.

And although there might seem to be nothing left to say in light of the mountains of documents filed in the case, “oral argument allows you to draw the judges’ attention to key points and address misconceptions that may have arisen,” Feldman said.

Still, no one is expecting surprises. Close watchers of the CRISPR case have their ears pricked for three pivotal points:

1. Should we even be here?

On Jan. 11, PTAB agreed to UC’s request for an “interference proceeding.” That’s where PTAB decides if two (or more) patent applications are based on such similar inventions that they overlap.

UC’s patent application, filed in March 2013, made 155 claims about “DNA-targeting RNA,” but not explicitly about using that system in animal, plant, or other eukaryotic cells. The Broad’s patent claim, filed in October 2013, specifically described using CRISPR to edit the genomes of eukaryotic cells.

PTAB apparently agreed with UC that extending Doudna’s work to eukaryotic cells was obvious to any skilled genome engineer, hence the Broad’s claims overlap with UC’s. But the Broad is expected to argue that CRISPRing plant and animal cells was far from obvious, that its patents therefore do not interfere with UC’s patent claims, and that an interference should therefore never have been declared.

If PTAB now agrees, reversing its January decision, it’s over. UC could, in theory, patent its non-eukaryotic inventions, the Broad would keep its 13 patents on CRISPRing eukaryotic genomes, and the legal bills (now north of $20 million) could stop accumulating. Since the most lucrative uses of CRISPR are expected to be in animals (including people) and plants, that would be a huge win for the Broad.

2. What are we arguing about, again?

The term for the invention that’s in dispute is the “count.” PTAB decided months ago that the count is the use of any form of CRISPR in any eukaryotic cell for the purpose of editing that cell’s genome.

UC is expected to argue that the count should be narrowed. If it can get the judges to agree that there are loads of separately patentable pieces of the CRISPR pie — tracrRNA, sgRNA, covalently linked RNA, or different bacterial sources of Cas9 — then it might be awarded patents on some of them. That would be a big win for UC.

3. Settlement, anyone?

There’s a lovely Westin just a hop, skip, and jump away from the PTO building in Alexandria, but don’t expect the lawyers to decamp to the bar and hammer out a settlement. The judges require the parties to periodically talk settlement, but none is in sight.

“There is so much money at stake and so much bad blood between the parties,” said Hastings’s Feldman. With both the Broad and UC having granted more than a dozen exclusive and non-exclusive licenses to their CRISPR technologies, she said, “the economic interests push in the same direction as the bad blood: a fight-to-the-death strategy.”

Tuesday’s oral arguments won’t be broadcast or webcast, and since reporters aren’t permitted to use electronics in the hearing room, don’t bother looking for real-time tweets. But within a week of the hearing, PTAB is expected to post a transcript on the case docket.

Republished with permission from STAT. This article originally appeared on December 5, 2016