GMSB at a stable vacuum and MSSM without exotics from heterotic string

We show that it is possible to introduce the confining hidden sector gauge group SU(5)′ with the chiral matter 100′ plus 5¯0′, which are neutral under the standard model gauge group, toward a gauge mediated supersymmetry breaking (GMSB) in a Z12−I orbifold compactification of E8×E8′ heterotic string. Three families of MSSM result without exotics. We also find a desirable matter parity P (or R-parity) assignment. We note that this model contains the spectrum of the Lee-Weinberg model which has a nice solution of the μ problem.