Reference for Chullin 267:12

ורב אסי אמר

only where [the purchaser] weighed them for himself,<span class="x" onmousemove="('comment',' In this case it was the purchaser who actually took away the priest's due, consequently the priest can only claim them from the purchaser and the latter in turn is entitled to an allowance in the purchase price.');">⁹</span>

Jastrow