A legal storm is threatening a startup backed by Bill Gates that wants to edit people's genes by 2017

A patent fight has been brewing over a new gene-editing technology that could be worth hundreds of millions, and it could throw a wrench in the plans of a company that just went public.

On Monday, Editas Medicine, the startup whose backers include Bill Gates and Google Ventures, filed for a $100-million IPO. But the vital patents the company holds - which surround its exclusive rights to gene-editing technology CRISPR - could soon be rendered worthless.

If a legal proceeding for settling patent disputes that was initiated in December moves forward, the company's patents could be revoked, Wired reports.

CRISPR, the hot new technology at the center of the controversy

The technology in question, known as CRISPR/Cas9, is a method for cutting and pasting DNA inside the cells of living organisms, including humans. The technique has been hailed for its potential to cure deadly diseases, modify crops, and even help scientists create genetically engineered designer babies.

Last November, Editas announced plans to use CRISPR technology in humans as early as 2017 to treat a rare form of blindness.

Two teams are claiming credit for discovering CRISPR - one led by Jennifer Doudna of UC Berkeley, the other led by Feng Zhang of MIT and the Broad Institute. Doudna's team filed for the first CRISPR patent, but Zhang's team paid to fast-track its own application, and was ultimately awarded the patent.

Editas's SEC filing references the disputed patents, and admits that "If we or our licensors are unsuccessful in any of these proceedings ... [it] could have a material adverse impact on our business."

"First to invent"

The dispute arises because both applications were filed while a somewhat archaic US law which granted patent rights to the "first to invent" was still in effect. On March 16, 2013, a new law took effect that changed this to the "first to file," the system used by most other countries.

In December of 2015, the Berkeley team filed what's known as an "interference proceeding." This is just a legal term for when there are multiple patent applications for the same technology, and a court must decide which party to award the patent to. As Wired points out, citing a blog post by New York Law School professor Jacob Sherkow, these proceedings are rare.

As Sherkow notes, Doudna's team filed their application on March 15, 2013, a day before the new "first to file" patent rules went into effect. Zhang's team filed theirs on October 15, 2013, but claimed they had invented the technology on December 12, 2012, under the old rules.

According to Wired, an appeals board still needs to approve this legal process, but is likely to follow the recommendation made in December.

The decision could come down to whether the patent covers the use of CRISPR to edit DNA, which Doudna claims to have invented, or its specific use in cells that have a nucleus (known as eukaryotic cells), which Zhang's team says it pioneered.

If the court decides in favor of Doudna and UC Berkeley, it could be bad news for Zhang - and for Editas.