Starbucks' limited-edition pink Stanley cups cause chaos as fans line up overnight to get their hands on the $50 mug at Target stores – with fights breaking out and resellers flogging cups for up to SIX times the price online

A limited-edition Stanley cup released in partnership with Starbucks is causing chaos in Target stores: fans line up overnight and fights break out in some locations.

The glossy pink version of the Stanley Quencher – an insulated cup that has proven to be a hit on social media – was released on Wednesday. People have flocked to Target stores across the US to get their hands on the $49.95 cup.

Resellers are already cashing in on the craze, with the item selling for as much as $299.99 on eBay – six times the retail price.

Although Stanley has been around since 1913, the stainless steel Quencher tumbler has become one of the most popular bottles in the world in recent years – and something of a cultural phenomenon.

The 40-ounce Quencher cup features a straw and handle — and the limited-edition pink Starbucks x Stanley version is the third mug release co-branded with the coffee chain.

Fans have flocked to social media to document waiting in line outside Target overnight to get the Cup.

Some even told how they waited in the freezing cold to make sure they didn't miss out on the exclusive item before it sold out.

In a videowhich has more than 1.6 million views, TikTok user Vincent Marcus documented camping outside a Target store from 1:40 a.m.

The shiny pink insulated cup was released on Wednesday and people have been flocking to Target stores across the US to get their hands on the $49.95 cup.

He said other people started lining up outside at 3 a.m., and the video showed a line snaking around the store before it opened at 8 a.m. Marcus added that customers were only allowed to purchase one cup each.

According to videos posted online, fights have also broken out in stores over the bottlenose dolphin.

One user posted a video – which has since gone viral – apparently shows a man jumping over the Starbucks counter and trying to steal some Stanley cups, before being tackled to the ground by another customer.

The cups are now selling on third-party eBay for as much as $299.99 – with some users listing the item for as much as $550.

“We are seeing an enthusiastic response to the Starbucks x Stanley Quencher and many stores are sold out,” said a Starbucks representative, who confirmed the item would not be restocked.

There was a similar frenzy when a co-branded red holiday cup was released in November, with customers camping and pitching tents in Starbucks parking lots.

Designed to keep drinks hot or cold for hours, the Stanley Quencher was first introduced in 2016.

Resellers are already cashing in on the craze, with the item selling for as much as $299.99 on eBay – six times the retail price

But it wasn't until the appointment of former Crocs president Terence Reilly — who helped revive and reinvent the shoe brand — to the company in 2020 that the cup began to gain cult status.

Stanley began marketing the tumbler to women and the Instagram generation, producing the Quencher in a range of color palettes.

Leveraging the power of social media influencers, the brand quickly came to be seen more as a fashion accessory, rather than a product originally aimed at workers.

The limited-edition pink Starbucks x Stanley cup is just one of more than 100 colors the brand now offers.

According to CNBCStanley's annual revenue is expected to exceed $750 million by 2023.