Update: It appears an "overzealous" Metallica attorney sent a cease and desist letter to a Canadian tribute act without the band's knowledge. "It turns out that a certain letter was delivered to the band Sandman that neither we nor our management were aware of until it surfaced online," Metallica tells Rolling Stone. "We have a long history of not only enjoying tribute bands, but we started as one. Heck, we even recorded a two-disc album of covers! ... Sandman should file the letter in the trash. Keep doing what you’re doing ... we totally support you! And in the meantime, our attorney can be found at SFO catching a flight to go permanently ice fishing in Alaska."

Metallica drummer Lars Ulrich even called Sandman's Joe Di Taranto. "He gave me and the band his full blessing to continue on as we were," says Di Taranto. "They want us to continue paying tribute to Metallica with their full blessing and approval. We will continue to fly the Metallica flag, loud and proud!!"

As we've seen over the years, Metallica have been very vigilant when it comes to protecting their trademark. And apparently that has landed a Canadian tribute band called Sandman on the radar of the band's legal team, who served them with "cease and desist" papers.

Warmachine's Joe Di Tarantino, who also sings and plays guitar in Sandman, revealed the news to fans on his Facebook page with a photo of the letter. He wrote, "So as some of you may or may not know, in my spare time from Warmachine, I play in a couple tribute acts ... One being a Metallica tribute called Sandman. Well last night when we arrived at the venue for our show in London, ON, we were served with 'Cease & Desist' papers courtesy of Metallica's lawyers. Quite funny! LOL!"

In the document, Metallica's legal team called out Sandman for using "official, stylized logos" and for promoting their live performances through Facebook and YouTube using the Metallica name.

After a number of comments on the Facebook post from followers, Di Taranto offered some clarification, stating, "Unfortunately I think many people here have either misread or not read the letter at all ... They don't want the band using the name 'Metallica' as in: 'Canada's Tribute to Metallica' nor the logo...Which has never been used. The FONT used as the Sandman logo however is the same font from St. Anger...which I guess they also have a problem with. Easy fix." Check out the post below.

Over the years, Metallica have defended their trademark in highly public cases like when Victoria's Secret began selling a lipstick called "Metallica" and with Nieman Marcus who sold a "Metallica" perfume.

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