JinkoSolar Sues Longi Over Back-Contact Cell Patent in Europe Court

• China’s JinkoSolar files second EU Unified Patent Court case against rival Longi, claiming infringement of premium back-contact technology.

Barely six months after its first salvo, JinkoSolar has launched a fresh legal attack on fellow Chinese giant Longi Green Energy, filing a complaint with the Unified Patent Court in Düsseldorf over alleged infringement of a former LG Electronics back-contact solar-cell patent.

The disputed intellectual property covers “selective-doping passivation layers” integral to n-type back-contact (BC) cells—an architecture prized for efficiency gains above 24 %. Jinko bought the global licence from LG after the Korean conglomerate exited module manufacturing in 2023 and is now asserting those rights as manufacturers race to commercialise BC lines.

The new suit targets Longi’s Hi-MO X6 module, unveiled in May with a claimed 25.3 % cell efficiency. Jinko alleges the product “reads directly on multiple independent claims” of the patent and seeks an EU-wide injunction plus damages. Longi dismissed the case as “meritless” and hinted at countersuits under its own 2,000-strong patent portfolio.

This escalation highlights the stakes as the industry shifts from PERC and TOPCon cells toward higher-margin BC technology. Analysts at Roth Capital warn that a court-ordered sales halt could scramble European procurement plans if either firm prevails. The UPC can issue region-wide remedies, shortening litigation timelines compared with country-by-country battles of the past.

Investors largely shrugged off the news—both stocks closed flat in Shanghai—but observers expect more courtroom drama as BC capacity ramps from 20 GW last year to a projected 120 GW by 2027. For buyers, the message is clear: check indemnities before signing module contracts.