Korean shipbuilder has lost an appeal in a patent case involving rivals Hyundai Heavy Industries and Samsung Heavy Industries.
The two patents involving LNG boil-off gas (BOG) re-liquefaction technology were found to be indistinguishable from the existing technology.
The case began in 2014 when Hyundai and Samsung both claimed DSME had registered systems widely used by shipbuilders.
The intellectual property trial and appeal board ruled in DSME's favour in 2015, but the patent court overturned this.
