TiAl3-type InPd3 crystallizes with the tetragonal I4/mmm (139) space group, having three independent positions i.e. In1 (2a), Pd1 (2b), and Pd2 (4d). InPd3-xCux (x = 0.1-0.9) adopts the same structure type, where Cu selectively substitutes the Pd1 (2b) position and at the limiting composition InPd2Cu, Cu completely occupies the same position (2b) and adopts the ordered VRh2Sn-structure type (Fig. , Table ). This was established by single crystal X-ray diffraction and first-principles DFT calculations in one of our recent publications . Here, our major focus is on the intriguing substitution pattern selected by the Cu-atom in the structure of InPd3.