401(k) non-elective safe harbor plan that excludes a small numer of NHCEs from making elective deferrals

[RWPHoenix]

I have a new client that has a safe harbor 3% non-elective plan that excludes NHCEs and HCEs of 2 of the three participating employers from making elective deferrals. The excluded employees are small in number and don't trigger a 410(b) problem and they do receive the SH contribution.  I have never had a plan with this type of exclusion.  I don't see anything in 1.401(k) -3(a-b) that prevents this but I thought I would ask if any one else has such a plan or an opinion on whether this works.

The plan is a multiple employer other plan because two of the employers are related and the third is unrelated. The two employers with the excluded employers are small with 10 or so employees while the third employer has over 400 employees all of which are eligible to make elective deferrals. Although the plan says it excludes all employees of the two small employers, I suspect that there are no HCEs employed by these employers.

Thanks for any insight you can give.

[ETA Consulting LLC]

The plan can be written to exclude any group of employees as long as they pass the appropriate test; 410(b) in this case.  But, whatever you're doing, it should be reflected in the plan's language; it should not be an arbitrary decision.

Not sure what you're asking.  I'm feeling there may be some missing details. 

Good Luck!