High 25 - Union Plan?

Does anyone know if the "high 25" rule (certain distribution restrictions to HCEs in a DB Plan) applies to a collectively bargained plan? I have an actuary who is suggesting it does not apply but am not finding any authority for that. 

The high 25 rule is part of 401(a)(4), specifically 1.401(a)(4)-5(b). Collectively bargained plans are typically treated as satisfying 401(a)(4), see 1.401(a)(4)-1(c)(5). So I would conclude that a collectively bargained plan is exempt from the high 25 rule.

Thanks, I think that's the ticket.