No, absolutely.  First and most important most of us will never will be 100 sure of the source of the unwanted gift.  Second it a risk (even with the use of protection) we should voluntarily assume when we choose to participate in this hobby.  Third, a TER poll indicates that of the only 50% of us who get tested, and of those who got tested most (56%) indicate have a least once tested positive for an unwanted gift.  Hence, one would suspect that such a list would be long as well as inaccurate.  It may be that if everyone listed everyone we suspected of giving us an unwanted gift their maybe nobody left to play with. Finally many of the unwanted gifts can be treated and it may be unfair to blacklist anyone because they may have had once an STD that no longer exists.  Rather than a black list, a better approached is assume everyone is a risk to you , use protection and only participate in activities that is compatible to the risk that you are willing to assume, get tested regularly and get treated if you test positive.