From left: Taylor Swift at the Billboard Awards, the Balmain jumpsuit on the srping 2015 catwalk, and Nasty Gal's version of the jumpsuit / Getty Images/Nasty Gal

The LA-based online shop has wrongly claimed the designer piece to be from its own-label. Fail.

Nasty Gal has wrongly taken the credit for the white jumpsuit Taylor Swift wore for the Billboard Music Awards on Sunday – and it’s got everyone talking.

The fast-fashion retailer posted on its social media accounts a photo of the popstar on the red carpet, claiming that she was wearing its own “Disco Inferno” jumpsuit – except she wasn’t. Instead, she was wearing an almost-identical piece from Balmain’s spring/summer 2015 collection.

Taylor Swift in a Balmain cut-out jumpsuit from the spring 2015 collection

Swift, who took home eight awards on the night, was part of Olivier Rousteing’s “Balmain Army”, alongside Kendall and Kylie Jenner, Lily Aldridge and Jourdan Dunn, all who helped the designer announce his upcoming collaboration with H&M at the event decked out in the label.

The LA-based online shop, founded by Sophie Amouruso, also author of the bestselling book Girl Boss, deleted the post later – probably after realising the mistake with followers commenting on the photo calling the label out for its error.

However, while the Balmain number costs a few grand, Nasty Gal’s jumpsuit is (well, was) for sale for $78 (approx. £50) – and unsurprisingly it has quickly sold out.

But this is not the first time that Nasty Gal has fallen into a copycat row. It is notorious for knocking off established and emerging designers, and earlier this year, it released a piece very similar to an Alexander Wang bodycon dress from the spring 2015 catwalk.

While it’s no secret that copying in fashion is endemic with high-street labels taking inspiration from, and in some cases virtually recreating, designer items, stores actually claiming that a luxury fashion house piece is one of their creations, is another story. This begs the question: where does inspiration end and intellectual property infringement begin?

Balmain's jumpsuit on the spring/summer 2015 runway.

“We can certainly conclude one of two things. Either Nasty Gal is so good at copying other brands' garments stitch-for-stitch that even its employees cannot tell the difference between the real thing and the copy, or Nasty Gal knew that Swift was wearing Balmain and was using this opportunity to sell one of its near exact copies,” said The Fashion Law.

We doubt Rousteing, creative director of Balmain, is too distressed, as he has praised in the past copycats such as Zara. Instead, this episode is likely to inspire him to include a similar piece in his capsule collection for H&M, which launches in November.

“I think it was Coco Chanel who said if you're original, be ready to be copied,“ Rousteing told The Independent last year. ”I love seeing a Zara window with my clothes mixed with Céline and Proenza! I think that's genius. It's even better than what I do! I love the styling, I love the story... I watch the windows always, and it's genius what they do today. They go fast; they have a great sense of styling and how to pick up what they have to pick up from designers. I'm really happy that Balmain is copied.”

Nasty Gal did not return a request for comment by The Independent.