European Patent Office Revokes Pacific Biosciences DNA Sample Prep Patent

NEW YORK (GenomeWeb) – The European Patent Office has revoked a patent held by Pacific Biosciences, the company's rival Oxford Nanopore Technologies said today.

Oxford Nanopore had challenged the validity of the patent, EP3045542, titled "Methods for nucleic acid sequencing," which was granted in 2016.

The patent relates to a method for converting a double-stranded DNA fragment into a circle by adding hairpin linkers at the ends, so that both the sense and antisense strand can be sequenced, an approach PacBio employs for its so-called circular consensus sequencing (CCS).

"The EPO ruled that the claims to a single molecule sequencing process were unsupported in the application and that the application only supported a template-directed synthesis sequencing method," Oxford Nanopore said in a statement. "As Pacific Biosciences was unwilling to accept this change, the patent was revoked."

Last spring, the companies settled a lawsuit in Europe involving the revoked patent as well as another PacBio patent, EP3170904, titled "Compositions and methods for nucleic acid sequencing."

Under the terms of that settlement, Oxford Nanopore would not sell its 2D sequencing products, which connect double-stranded DNA with a hairpin, in the UK or Germany through the end of 2023 and the company dismissed a countersuit it had filed against PacBio. Oxford Nanopore had already discontinued the use of 2D sequencing in 2017, replacing it with so-called 1D² read sequencing.

Also last year, the US International Trade Commission determined that Oxford Nanopore's products do not infringe a number of PacBio's US patents.

"The decision by the EPO is consistent with a recent decision by the International Trade Commission (ITC) to limit the claims of a related Pacific Biosciences US patent to template-directed synthesis," Oxford Nanopore said.

The companies are still involved in patent litigation in the US, where PacBio has sued Oxford Nanopore for infringing several of its patents.

A PacBio spokesperson said the company has no further comment at this time.