The Milk Development Council is fighting to protect the image of the milk moustache as a trademark.
It wants to prevent the image being misused by other industries but has run into difficulty because the UK Trademarks Registry said the image was not distinctive enough. The MDC must supply evidence to the contary to win its case.
"We're doing this on behalf of the industry," said Vicki Hathaway at the MDC. If the trademark had been in place last year, the MDC would have challenged Nestlé over a cappuccino ad featuring a woman with froth on her lip.
"This creates confusion in consumers' minds, and that's not what we want," she added.
The MDC is appealing for industry figures to support its claim by testifying about the distinctiveness of the milk moustache.
The campaign is a collaboration between five Scottish dairies and the MDC.