A multistage MMIC power amplifier with diagonal oriented field effect transistors (FETs) provides higher power output for a smaller MMIC die size. Corporate feed structures divide the RF input signal and combine the RF output signals and in a base two fashion. The corporate feed structures allow the FETs of the amplifier stages operate in-phase with adjacent circuitry appearing as an even-mode open circuit. The MMIC power amplifier is suitable for applications where reduced size, high efficiency and high gain are important, such as in commercial communication systems.