Taylor Swift's signed 'Midnights' guitar is up for auction.

The 'Shake It Off' hitmaker's acoustic boasts a picture of the star laying down on the couch and, at the time of writing, the highest bid is $5,500.

The money raised from the sale of the instrument will benefit war veterans suffering from PTSD.

It's part of the Raven Drum Foundation’s second annual 12 Drummers Drumming sale, which runs until December 12.

The non-profit was founded by Def Leppard drummer Rick Allen and his wife Lauren Monroe.

Meanwhile, Taylor's fans are suing Ticketmaster for "price fixing" and "fraud".

Following the ticket-buying debacle for the superstar's North American 'Eras' tour, which saw Ticketmaster cancel the general sale due to high demand and insufficient ticket inventory, a number of fans are now suing the company.

According to TMZ, the firm is being sued for "fraud, price fixing and antitrust violations", as well as "intentional deception", after scalpers scooped up a large number of tickets.

The lawsuit claims that because Ticketmaster is involved in both the primary ticket sale market as well as the secondary market, they were "eager to allow" scalpers into the presale event.

Ticketmaster previously issued an apology to Taylor and her fans, following the pre-sale debacle.

It read: "We strive to make ticket buying as easy as possible for fans, but that hasn’t been the case for many people trying to buy tickets for Taylor Swift ‘The Eras’ Tour. First, we want to issue an apology to Taylor and all of her fans – especially those who had a terrible experience trying to purchase tickets."

The apology came after Taylor revealed she was "p***** off" with how the sales had been handled.

She wrote in an Instagram message to fans: "I’ve brought so many elements of my career in-house. I’ve done this SPECIFICALLY to improve the quality of my fans’ experience by doing it myself with my team who care as much about my fans as I do. It’s really difficult for me to trust an outside entity with these relationships and loyalties, and excruciating for me to just watch mistakes happen with no recourse.

"There are a multitude of reasons why people had such a hard time trying to get tickets and I’m trying to figure out how this situation can be improved moving forward. I’m not going to make excuses for anyone because we asked them, multiple times, if they could handle this kind of demand and we were assured they could. It’s truly amazing that 2.4 million people got tickets, but it really p***** me off that a lot of them feel like they went through several bear attacks to get them."