The reaction of [Pt(C2H4)(PPh3)2] with P4S3 yielded the trinuclear platinum complex [{Pt(µ-P4S3)(PPh3)}3]·C6H6 whose structure has been determined by X-ray diffraction. Crystals are triclinic, space group P1.macr;, with Z= 2 in a unit cell of dimensions a= 21.414(12), b= 15.450(9), c= 15.670(9)à , α= 121.71(9), β= 94.22(8), and γ= 107.50(9)°. The final R factor was 0.069 for 3 990 independent observed reflections. Insertion of a metalâ ligand moiety into a Pâ P bond of the cage molecule occurs and a trinuclear structure is formed by sharing one P atom from such a bond between two Pt atoms. The Pt â ¯ Pt separations range from 4.05 to 4.22 à and the mean P â ¯ P distance after cleavage is 3.03(3)à .