Two fight, the third benefits

What is a classic saying for a third party getting all the benefit while two others are fighting.

For example (from wikipedia): Two dogs fight for a bone, but a third one runs away with it.

According to the [Oxford Dictionary of Proverbs][1], the moral is embodied in the story of the lion, the bear, and the fox, which is included in many post-medieval editions of Aesop's Fables.

Early reference: c 1386 Chaucer / Knight's Tale: "We strive as wide the hounds for the boon.... There cam a kyte, while that they were so wrothe, And baar awey the boon betwixe hem bothe.

Further references in 1534, 1639, etc.