Bidfood said registering the word would exclude other brands in New Zealand from using it for their own products, and even has its own brand of plant-milk milks under the brand name "Barista Federation".
Granted none of these brands used "barista" in relation specifically to oat milk but Bidfood said it would be "an odd result" if it could be used for oat but not other dairy milk alternatives.
One of its primary arguments against the trademark being granted was that for the average consumer a barista is someone who makes coffee professionally.
To associate it with one brand of plant milk could potentially give that milk an unfair advantage in the market because by comparison other plant milks would be less suitable to heat and serve with espresso coffee.
Bidfood's fundamental submission was that the evidence establishes the word "barista" cannot be itself distinctive of one trader in New Zealand.
"The term 'barista' is purely descriptive, and cannot do the job of distinguishing Oatly's goods from those of other traders," it said in submissions to the IPO.
Expert witness Dr Valentyna Melnyk from the UNSW Business School in Sydney, was brought into the hearing earlier this month to give evidence on the issue.
She said the word barista was likely to make consumers think that milk substitute products - like Oatly's - were more likely to be associated to a premium product because of its link to coffee-making professionals.
"To the extent that consumers believe that coffee made by a professional barista - as opposed to a regular person - has a better taste," she said.
Melnyk said it could also have an effect on suppliers as using the word could imply that their oat milk was more suitable than other brands to be used in a professional setting.
As part of her evidence Melnyk said that producers and consumers alike were already using "barista" as a sub-category within different types of milk rather than between different brands.
The Intellectual Property Office ultimately agreed with Bidfood and with Melnyk and said consumers would expect "a word used for one type of dairy substitute (e.g. soy) to have exactly the same meaning when seen in the context of oat milk."
"Dairy substitutes are to an extent competitive with each other, sold alongside each other, and may therefore be directly compared by consumers," it said in its decision.
"This is also consistent with Dr Melnyk's observation that "dairy substitutes mimic the trends set by consumer demands in dairy," 82 which does not distinguish between different types of dairy substitutes."
Oatly raised nearly $1.4 billion when it debuted on the US stock market last year and in 2020 raised over $200 million in an investment round lead by Portman and Oprah.
