coupon excluding MAP pricing

[jnnjr]

I know many stores use coupons to get around MAP pricing, but we have a manufacturer that is pretty strict regarding this. Does anyone have any ideas on how to exclude a coupon from being used against these items?

The best way I can see is to mark them as a separate manufacturer and use the exclude from manufacturer feature within the promotion manager. Is this the only way to exclude items from a coupon's use?