(Changes headline, first paragraph to show Monsanto liable, not "guilty", in the civil court ruling)
LYON/PARIS, France, Sept 10 (Reuters) - A French court upheld on Thursday a 2012 ruling in which Monsanto was found to be liable in the chemical poisoning of a French farmer, who says he suffered neurological problems after inhaling the U.S. biotech company's Lasso weedkiller.
The decision by an appeal court in Lyon, southeast France, confirmed the initial judgment, the first such case heard in court in France, that ruled Monsanto was "responsible" for the intoxication and ordered the company to "fully compensate" grain grower Paul Francois.
Monsanto's lawyer said the company would now bring the decision before France's highest appeal court.
(Reporting by Catherine Lagrange and Sybille de La Hamaide, editing by Gus Trompiz and Susan Fenton)