What is the amount of bleeding allowed before a referee can stop a fighting?

[Beercules]

First drop of blood I see and I'll stop the fight.

[Bolopunch68]

When blood coming from a cut near the eye that it affect the vision of the fighter. Bloody nose ref/doc will let the fighter go still. Broken jaw is up to the fighter or the doctor. Bloody face is normal especially if the fighter cuts easy. So, blood is not really a measuring stick for the ref to stop the fight.

[Eastcoast]

All depends where they're bleeding and how they're responding.

In his first fight with Edison Miranda, Arthur Abraham was said to have lost nearly a liter of blood. If you watch the fight, you see it just running out his mouth from the middle of the fight to the end.

http://sports.espn.go.com/sports/box...ory?id=3453494


Against Casamayor, Diego Corrales was stopped due him hyperventilating from blood running down his throat due to a cut in his mouth.

And against Juan Marquez, Robbie Peden started puking blood after a body shot.