A stiffener for reinforcing a package integrated circuit. The stiffener includes a rigid planar element having a first surface for bonding to a package substrate. The rigid planar element forms a major interior aperture for receiving and surrounding an integrated circuit on all sides of the integrated circuit. The rigid planar element also forms a minor interior aperture for receiving and surrounding a secondary circuit structure on at least three sides of the secondary circuit structure. In this manner, the stiffener provides structural support to the integrated circuit package, which reduces and preferably eliminates twisting and warping of the substrate package as it heats and is subjected to other stresses. Because the major interior apertures does not need to be large enough to fit both the monolithic integrated circuit and the secondary circuit structure, there is more stiffener material available to provide structural support than there would be if the major interior aperture was large enough to fit both the monolithic integrated circuit and the secondary circuit structure.