Napa-based Waugh Family Wines on Friday said it has sued Bronco Wine Co., which has a large south Napa Valley bottling operation, claiming trademark infringement on Waugh’s Six Degrees Wine brand.

Waugh said it filed a federal lawsuit over Bronco’s “6° Six Degrees” brand. Waugh started its brand, a cabernet sauvignon wine that retails for $150 a bottle, with the company in 2005. The Bronco brand, which has pinot noir, chardonnay and rosé wines and retails for $10–$15 a bottle, is said to have hit the market in 2013.

Ryan Waugh, owner and winemaker, claims Bronco’s brand is “potentially wreaking havoc on the value” of Waugh’s brand and “creating substantial confusion in the marketplace.”

“My wife and I are sickened by the long-term implications of Bronco’s use of the 6° Six Degrees brand, which is mass-produced and sold at pennies on the dollar, compared to our ultrapremium brand,” Waugh said. “Over the last decade, we’ve put everything on the line to ensure our brand’s success, and we’re watching 10 years of blood, sweat and tears unravel before our eyes.”

The 6° brand, owned by Panther Rock Wine Co. and not Bronco, has been sold nationwide for “a number of years” and is a registered U.S. trademark, said the defendants’ attorney, Peter Brody of Washington, D.C.-based Ropes & Gray. He said the 6° and Six Degrees brands are “readily distinguishable by the consumer” and neither Waugh nor his company previously objected to the registration or the brand.

“It is puzzling why Mr. Waugh is only now coming forward with his objection,” Brody said in an email. “I note in this regard, however, that while although Mr. Waugh’s press release talks about the parties’ discussions of a potential resolution of the dispute, he neglects to mention that he proposed to withdraw his objection to Panther Rock’s brand — as long as Panther Rock pays him a substantial sum of money. That does not sound like someone who is concerned about alleged ‘consumer confusion,’ as he claims in his lawsuit.”

Joey Franzia, Damon Franzia and Brian Franzia and 10 other siblings and cousins of the fourth generation of the Franzia family started Panther Rock in 2009. The Franzia family started Bronco in 1973.

Waugh claims the dispute started early last year, when Waugh began receiving phone calls, emails and in-person requests for varietals never produced under the Six Degrees brand. He said he searched the Web and discovered Six Degrees Cellars connected to the 6° brand.

Waugh insists his wife, Crystal, and he reached out to Bronco in June to resolve the matter.

“We hoped to avoid the lawyers by coming to a consensus from the get-go, but instead of working with us, Bronco has pushed ahead, doubling down on their product in spite of us — and in doing so it appears they’re intentionally undermining us in the market,” Waugh said.

The case, JC Waugh Wine Co. LLC vs. Bronco Wine Company, is set to go before federal judge Edward Chen in San Francisco on March 9.