Chinese module maker JinkoSolar and Norwegian/Asian manufacturer REC Group have jointly filed a petition with the U.S. Patent Trial and Appeal Board seeking an inter partes review – the procedure for challenging the validity of a U.S. patent – for patent number 9,893,215 B2, which Korean rival Hanwha Q Cells claims Jinko and REC have infringed.

The petitioners said Hanwha’s claims on the patent “method for manufacturing a solar cell with a surface-passivating dielectric double layer, and corresponding solar cell” are technically unfounded, due to ‘prior art’ – evidence an invention is neither new nor “non-obvious” before the filing of patent applications.

“As the petition explains, claims 12-14 of the 215 patent are invalid as anticipated by, or obvious in view of, the prior art,” Jinko said in a statement yesterday. “All of these grounds are distinct from the unpatentability grounds presented in the separate IPR [inter partes review] petition filed by Longi Solar on May 13, 2019.”

Fellow manufacturer Longi, which is also the subject of a patent infringement claim by Hanwha, has separately disputed the basis of the Korean manufacturer’s patents.

“Patent should be declared invalid”

Jinko said Hanwha’s patent should be declared invalid in light of five, unspecified prior art grounds. “The fact that all three respondents in the ITC [U.S. International Trade Commission] action challenge the validity of this single patent on multiple, independent grounds, further demonstrates the weakness of Hanwha’s case,” said Jinko CEO, Kangping Chen. “We believe that the 215 patent is invalid and Hanwha Q Cells’ allegations of infringement are unjustified,” added REC chief executive Steve O’Neil.

Hanwha Q Cells lodged a patent infringement lawsuit against Jinko and REC in Germany, and two more against the same companies plus Longi in the U.S in early March. In its lawsuit the Korean manufacturer said its rivals were using its patented solar cell passivation technology to increase the efficiency of their products, and has asked for trade authorities to bar imports of these products.

Jinko categorically refuted the allegations and said it did not expect disruption to normal operations as a result of the lawsuit. Longi stated there was considerable uncertainty over the validity of the patents at the root of the lawsuits. REC said it intended to investigate the matter and take legal action against the Hanwha lawsuits.

In mid-March, Hanwha Q Cells also brought patent litigation in Australia.