Multiple supermassive black hole (SMBH) systems have long been predicted to play an important role in galaxy evolution and dominate the stochastic gravitational wave background spectrum in the nHz-microHz frequency range. However, observational constraints on these impacts are limited since very few low separation binary (or multiple) SMBH systems are known. I will present our recent discovery of a triple SMBH system at z~0.4. This includes a ~140 parsec (26 milli-arcsecond) separation inner binary, which is roughly an order of magnitude lower separation than known binary/dual SMBH systems at comparable redshifts (with direct imaging confirmation). This discovery suggests that close-pair binary SMBHs are more common than previous observations suggest and that their radio-jet morphology may be an efficient way to find similar systems.