We present a scaling theory of self-assembly of triblock ter-polymer ABC in selective solvent which is good or theta for both terminal blocks A and C, but poor for the middle block B. It is demonstrated that depending on the level of incompatibility between blocks A and C of the ter-polymer, equilibrium micelle has either laterally homogeneous (mixed) or segregated ("Janus") corona. (C) 2013 Elsevier Ltd. All rights reserved.