  We list operators of the superpotential of the effective MSSM that emerges
from the NMSGUT up to sextic degree. We give illustrative expressions for the
coefficients in terms of NMSGUT parameters. We also estimate the impact of GUT
scale threshold corrections on these effective operators in view of the
demonstration that $B$ violation via quartic superpotential terms can be
suppressed to acceptable levels after including such corrections in the NMSGUT.
We find a novel $B, B-L$ violating quintic operator that leads to the decay
mode $n\to e^- K^+$. We also remark that the threshold corrections to the Type
I seesaw mechanism make the deviation of right handed neutrino masses from the
GUT scale more natural while Type II seesaw neutrino masses, which earlier
tended to utterly negligible receive threshold enhancement. Our results are of
relevance for analyzing $B-L$ violating operator based, sphaleron safe,
Baryogenesis.
