Hampshire anglers Wayne Comben and Graeme Pullen decided to let the rare estimated 550lbs fish go after it dragged their boat for more than a mile off the coast of Boscastle in Cornwall and took 90 minutes to reel in.
Pullen told the BBC there was a “crazed feeding frenzy…I have never seen anything like it in 40 years of sea fishing,” after the duo dropped bait into the sea.
The Porbeagle is the big daddy of the mackerel family. It lives on a diet of small to medium sized fish.
The largest shark ever caught in British waters was a record 507lbs – in order for the record to have been beaten the anglers would have had to land and kill the shark, which they chose not to do.
Very few shark attacks have been blamed on Porbeagles – it is now listed in some parts of the world as an endangered species, due to its popularity and value for fishermen.
“With an animal listed as vulnerable and under such immense pressure as the porbeagle, it would be morally unethical to kill it.” said Dr David Gibson of the National Marine Aquarium in nearby Plymouth.
Watch footage of the shark below…
Main image: YouTube/BBC