Bava Batra 85 - One's Container Formalizes Acquisition
Rav and Shmuel both said, "A person's container can formalize acquisition for him in any place - except in the public domain." Rabbi Yochanan and Resh Lakish both said, "Even in the public domain."
A person's container can act as his courtyard to acquire items that are placed in it, provided that the container is placed in a domain where the container 's owner has the right to place it. Thus a buyer can acquire items in the seller's domain by placing them in his container , provided that the seller gives him the right to place the container there. One can place containers in the public domain also - but not keep them there permanently.
However, they don't argue. The first ruling is dealing with a public thoroughfare, and the second - with the quiet recessed area of the public domain, to which people step to discuss business.