Beatrice wore the Philip Treacy creation for the wedding of her cousin Prince William to Kate Middleton last month, following which she decided to auction off the accessory to raise money for both UNICEF and Children in Crisis.
According to The AP, the auction closed out early today at $130,000 to a currently-unknown winner.
The eccentric headpiece had been described as being similar to both a pretzel and a pair of deer antlers.
"I've been amazing by the amount of attention the hat has attracted," Princess Beatrice wrote on the eBay listing. "It's a wonderful opportunity to raise as much money as possible for two fantastic charities.
Several celebrities have admitted to placing bids on the hat, including Australian children's presenters The Wiggles and Dragon's Den star Duncan Bannatyne.