The attack happened in 1997 and, since then, not only has Matt continued surfing using a prosthetic limb, he's also become an activist campaigning for the conservation of sharks.
According to the Daily Mail, Mike works as a professional photographer, with his pictures being featured in The Wall Street Journal, Hawaii Magazine, Discovery Channel and other media.
And he often shares his inspirational pics on Instagram, showing himself still surfing, as well as stunning views of Kaui and its nature.
Next to one he wrote: "This afternoon. The board broke on this wave but worth it."
Another shows him tackling a wave at a "Neat angle".
And another describes his "sassy monday morning".
Coots' amazing story of survival has been told many times since it occurred in October 1997.
The shark swam up vertically from beneath Mike while he was sitting on his board.
It grabbed his right leg in its mouth and started shaking it like a rag doll. According to the Huffington Post, Coots said: "I got this really creepy feeling. It was an incredibly creepy, spooked out, get-away-from-me feeling."
He was rushed to hospital and said when he woke up he was "just really happy to be alive".
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