Trainer David Pipe has confirmed that Comply Or Die has passed away at the age of 17.
The gelding will be best remembered for his triumph at the 2008 Grand National.
"He provided me with the highlight of my career to date when winning the 2008 Grand National at Aintree and ran another fantastic race when runner-up the following year," Pipe wrote on his blog.
"He was a tough, genuine and lovable horse and I was delighted to see him looking so well at the Grand National parade of former winners only last month. He is a horse I will always hold dear in my heart and I am greatly saddened to hear of his loss."
During his racing career, the son of Old Vic won eight races and raked in £798,809 in prize money.
