How can you tell if the user thats sending you an offer got there by clicking on a promoted listing?

[medelste]

How can you tell if the user that's sending you an offer got there by clicking on a promoted listing? If they didn't click on a promoted listing - and so I won't pay eBay the promoted listing fee, I'd be willing to accept a lower offer. If they did click on a promoted listing - and so I will have to pay eBay the promoted listing fee, I'd want to stay more firm on my asking price. Yet I don't see that information!