Palladium(II)-induced selective B(4)−H activation of an o-carboranylthioamide has been developed. A tetranuclear palladium(II) complex has been obtained in high yield with excellent regioselectivity. DFT calculations have confirmed that the B(4)-borometalate is lower in energy than the corresponding B(3)-borometalate. The product proved to be a good precursor for target mononuclear or trinuclear B(4)−H activated complexes.