This paper is concerned with identifying linear system dynamics without theknowledge of individual system trajectories, but from the knowledge of thesystem's reachable sets observed at different times. Motivated by a scenariowhere the reachable sets are known from partially transparent manufacturerspecifications or observations of the collective behavior of adversarialagents, we aim to utilize such sets to determine the unknown system's dynamics.This paper has two contributions. Firstly, we show that the sequence of thesystem's reachable sets can be used to uniquely determine the system's dynamicsfor asymmetric input sets under some generic assumptions, regardless of thesystem's dimensions. We also prove the same property holds up to a sign changefor two-dimensional systems where the input set is symmetric around zero.Secondly, we present an algorithm to determine these dynamics. We apply andverify the developed theory and algorithms on an unknown band-pass filtercircuit solely provided the unknown system's reachable sets over a finiteobservation period.