Me: HMMMM Last Name
Caller: Hi, is this HMMM Last Name?
Me: Yes it is.
Caller: Hi, How are you.
Me: I'm well.
Caller: That's good. Did I catch you at a good time?
Me: May I ask what this is concerning.
Caller: My name is X and I'm calling on behalf of 22 company.
Me: OK, how can I help you?
Caller: 22 comapny provides blue, yellow, and green services and I'd like to discuss how we can do business with your company.
Me: I'm sorry, I'm not responsibile for those activities at my company. Thanks, <click>
Stop the conversation there. Their job is to try to get you involved or give you the name of the person who IS responsible. If you are not going to do that, then save them time and let them get to their next call.