The present state of art in search for T-violation in neutron induced reactions is briefly observed. The interest is focused on one interesting and still not well understood result, which is a recent observation of a non-vanished T-odd triple correlation in ternary fissionD(233U)=(−1.8±0.1)×10−3andD(235U)=(+0.52±0.06)×10−3.The puzzle is a value quite large even for the mimic final state effect. Since the theoretical estimation of the latter is rather complicated due to the fission complexity, we discuss an experimental approach to reveal the origin of this correlation. ©2000 American Institute of Physics.