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The online marketplace allows anyone to sell their handcrafted goods - a kind of boutique eBay. It's popular with fan communities like Swift's, and there are numerous t-shirts, pictures, candles and other items on the site emblazoned with the singer's image and lyrics.
But Swift has had enough, and is issuing cease-and-desist letters to many sellers on the site.
It's important to note that Etsy doesn't make these items themselves. Anyone can sell their products on the site without prior approval from the company, or even their knowledge. But the company does have a duty to respond to objections and potential legal issues if they don't want to be held responsible for potentially illegal content sold on its site. (It's the same reason YouTube deletes copyrighted material from its site.)
At this point, there's no indication that Swift is threatening to take legal action against Etsy itself.
One seller told BuzzFeed that fans "see themselves as part of the artist's story, however small. They want to contribute and be creative and have fun." While they recognise the artist's intellectual property rights, they say that the action "leaves us with a bitter taste in our mouths. It feels as though we don't matter, that our ideas and creations never belonged to us in the first place... And for other fans who make art, I'm afraid this is going to be the future."
Etsy
Another seller said they were "shocked" by the crackdown. "We didn't feel as if it had become popular enough to cause harm to Taylor Swift's empire... We didn't even make enough money for a lawyer and this seemed like a harmless and fun idea."
"We grew a little angry and felt targeted by her camp," they added.
It's rare for Taylor Swift to anger her fans, even inadvertently. The singer goes to great lengths to cultivate and support her following, including sending them hand-wrapped Christmas gifts, and helping one to pay off her student loans.
But Swift is also in the process of cracking down on unauthorised uses of her personal brand. She's recently applied to trademark several famous lyrics from her songs. These include "this sick beat" and "nice to meet you, where you been." That could mean that she plans on releasing her own merchandise featuring those lyrics in the future. Swift has reportedly been taking some action against Etsy sellers before this, however. The earliest takedown notice BuzzFeed saw dates from 2013.
There was also a similar incident with Beyoncé in January. The singer reportedly threatened to sue Etsy itself over mugs sold on the site with the word "Feyoncé" on them - a play on the words "Beyoncé" and "fiancé."
Etsy has issued the following statement:
Because of privacy and legal concerns, we can't verify specific information about who contacts us. However, I can share more information about our copyright and intellectual property policy:
When a seller opens a shop and lists an item on Etsy, they are agreeing to our terms of use, including trademark guidelines, and copyright and IP policy. We take intellectual property and copyright concerns very seriously, and we comply with the DMCA and remove items when we have proper notice. When we are notified about allegedly infringing material, we act swiftly and in compliance with our policy, which you can find here.