SAP SRM Bidding RFX difference between invited bidders and participated bidders

Hi Experts,

We are working on public RFX where one of the requirement is to identify invited bidders and bidders who directly participated in public RFX by registering it first. I checked all entries related to Business partner but did not get any major characteristic field which can differentiate this.

Is this possible via standard RFX solution available?

Best Regards,

Kunal Sanghavi