Castore has been valued at almost £1bn after it raised around £150m from three new investors.
The Manchester-based sportswear brand has been backed by US merchant bank and investor The Raine Group, which led the funding round, as well as New York and Tel Aviv-headquartered Hanaco Ventures and venture capital firm Felix Capital.
The fundraising is the largest in the company's history and values it at £950m. The business was founded in Liverpool by brothers Thomas and Phil Beahon and counts the likes of Andy Murray and the billionaire Issa brothers among its existing investors.
READ MORE: Castore creates hundreds of jobs as profits almost double at Andy Murray-backed sportswear brand
In a statement posted on LinkedIn, Thomas Beahon said: "Today Castore announces the successful completion of a c£150m capital raise, one of the largest growth capital investments in the world in 2023. We are immensely proud to achieve this milestone which represents a huge endorsement of our business model and strategy and this would not have been possible without the passion, commitment and hard work of all our amazing staff who we massively appreciate.
"We are delighted to welcome The Raine Group, Felix Capital and Hanaco Ventures on board as partners, all of whom we have no doubt will add significantly value as we take Castore through the next stage of growth and become a truly global brand. Castore is a true entrepreneurs story - when my brother and I co-founded the business in 2016, nobody thought we had any chance of being successful - banks, investors, advisors and everyone else we spoke to rejected our idea as crazy.
"Eventually our mum and dad told us they believed in us and would re-mortgage their home to give us the money to get Castore off the ground - an amazing gesture and show of faith only a parent can have. Equally, knowing if you fail you won't just be failing for yourself, you will have a significant impact on your parent's lives, puts a level of fear and anxiety in your stomach that few people will understand. We didn't just want Castore to be successful, we needed it to be.
"There is a business side to our story - seeing a gap in the global sports market and using technology and data to create a superior model to the existing brands who had dominated the sector for a generation; but the bigger aspect is the personal side - a story of passion, work ethic, big dreams and most importantly - never, ever giving up. People rarely talk about the difficult times but they are far more important than the good moments and how we respond to adversity is how we all become who we are.
"Our vision when we founded Castore was to create a proudly British brand competing on the global stage and we won't stop until we get there."