Charles Ellicott Commentary Exodus 21:35-36

"And if one man`s ox hurt another`s, so that it dieth, then they shall sell the live ox, and divide the price of it: and the dead also they shall divide. Or if it be known that the ox was wont to gore in time past, and its owner hath not kept it in, he shall surely pay ox for ox, and the dead [beast] shall be his own." — Exodus 21:35-36 (ASV)

if one man’s ox hurt another’s. —Where no blame attached to the owner, the loss was to be equally shared. Where the dangerous character of the animal was, or ought to have been, known, the man whose ox was killed received its full value.