Did you catch this in the article? It's a record because it's the only recorded speargun killed halibut in AK. It could weight 5 lb and still be the record.

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The freediving instructor says it’s the first recorded Pacific halibut taken by speargun, and he expects the International Underwater Speafishing Assn. to approve the catch as a world record.

“In a time of deceit telling the truth is a revolutionary act.”
― George Orwell

It's not over when you lose. It's over when you quit.