MB4 262b: Your Animals and Hilchos Techumim (397:5-10)

If a person gave his animals to two different shepherds the animals retain the techum of the owner.

If he gave to two shepherds on Shabbos the animals retain the techum of the owner.

An ox of a פטם (fattener) goes according to the techum of the purchaser.

An animal jointly owned by brothers goes according to the techum of both (restrictive).

Techum for a jointly owned barrel of wine or animal where each owner has a different techum.