'Taco Tuesday' is actually trademarked, and harshly policed with legal threats from a taco chain based in Wyoming

• The widespread "Taco Tuesday" slogan is in fact a 30-year-old trademark, which its owners are prepared to defend with legal action.
• Wyoming-based chain Taco John's registered it in December 1989, and have rights to it everywhere in the US except New Jersey.
• The usefulness of the trademark is in doubt as experts say "Taco Tuesday" is so common no one associates it with just Taco John's.
• A feud currently playing out between Taco John's and a brewery five blocks from their Wyoming HQ has brought ownership of "Taco Tuesday" into the spotlight.
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The widespread "Taco Tuesday" slogan is actually a 30-year-old trademark, and one which its owner, a taco chain based in Wyoming, is prepared to vigorously defend.

Taco John's trademarked the slogan in December 1989, and has rights to it across the whole US except New Jersey, where a state-wide trademark on the slogan already existed.

After decades spent firing-off cease-and-desist letters to companies using the tag-line, its future is in doubt after Taco John's pursued a brewery near their offices in Cheyenne, The Associated Press (AP) reported.

Taco John's sent Freedom's Edge Brewing Co a cease-and-desist letter in July.

The message said that they are aware "Taco Tuesday" is often used "inadvertently" but that "it is still extremely important to us to protect our rights in this mark."

The brewery, in response, posted a response to Facebook:

"We have nothing against Taco John's but do find it comical that some person in their corporate office would choose to send a cease and desist to a brewery that doesn't sell or profit from the sales of tacos."

Legal experts say the term has become so widespread - known as "genericide" - that there is little chance to succeeding in court. The phenomenon has already taken place with "escalator" and "nylon."

Michael Atkins, an attorney in Seattle, told the AP: "It's kind of asinine to me think that one particular taco seller, or taco maker, would have monopoly rights over 'Taco Tuesday"."

"It has become such a common phrase that it no longer points to Taco John's and therefore Taco John's doesn't have the right to tell anybody to stop using that."

Taco John's ex-chief marketing director Billie Jo Maara called the slogan the company's "DNA" in a 2016 TED talk, AP reported.

Business Insider contacted Taco John's for comment, but is yet to receive a response.