We have a secondary market loan officer that wants to advertise with a local realtor. He, personally, not the bank will pay for the ad or split the cost of the ad with the realtor. Is this a RESPA violation sincethe bank's name will be on the ad even though the bank isn't sponsoring it? Any help would be appreciated.

IMO yes. Even though this loan officer is doing the advertising, wouldn't the referrals from the ad actually be to the bank itself (such as see Joe Smith at ABC Bank)?