It submitted nine grounds for opposition - all of which were rejected by the assistant commissioner of trademarks, Jennie Walden, in a decision made public yesterday.
Osawa had also submitted its wine for trademark in Japan and Australia, which Baron Philippe de Rothschild had also demanded it withdraw.
Mark Lim, director of Osawa Wines, which is based in Maraekakaho, west of Hastings, said he was pleased with the decision.
"It's been a very trying and emotional time for us, in which we were uncertain about the future of our brand, so we're relieved that at last it has been resolved."
The name came from a combination of things, he said.
"The sheep farm we converted into a vineyard, the white cumulus clouds floating over Hawkes Bay, the affection for the French style of wine of the winery's owner, Mr Osawa, and the winemaker Rod McDonald's own background in the French style of winemaking."
It is unclear where the "Mouton" in the French estate's name originated, but it was part of the property's name when it was bought in the 1880s by Nathaniel de Rothschild of the banking family, when it was known as Chateau Brane-Mouton.
Mouton means sheep in French; it has been suggested the animals may have once grazed on what became the estate's vineyards.
The name instead be derived from the Old French word "motton", for hill, as the chateau is on a small rise.
