There's a lot of talk in online forums right now, between eBay PowerSellers, primarily those selling books and courses telling how to make money on eBay.
A string of comments I spotted today originated from one PowerSeller stating he had been asked for his eBay ID, so a person, purporting to be a potential book buyer could check the book seller's actual success against profits he claimed to be making on eBay. Within days a whole string of negative feedback points arrived for the PowerSeller, all from different eBay buyers.
After days of gruelling investigation, it transpired the individual seeking this person's ID was also an eBay PowerSeller, although he had not left feedback from his own account for fear of being exposed and reported to eBay. Instead he had enlisted 'friends' to open accounts, buy from our victim and then leave negative feedback.
Several major PowerSellers reported similar problems, all having given their eBay IDs to untraceable individuals who subsequently recruited others to leave negative feedback for the victim in order to make their own accounts look good by comparison.
So it's a hot argument: do you or don't you give out your eBay ID? I always did and I know other PowerSellers who still do and haven't encountered problems, yet!
And before I move on, yes I have fallen victim to this awful practice, in one case receiving four negatives within days of someone asking for my ID which I gave. This one, not so cute or clever as today's operators, left negative feedback from his own eBay account before he had even been invoiced or paid for the products. eBay removed the feedback points and expelled the offender the very same day.
It really is up to you what you do about revealing your ID, but I suggest you confirm the email address of the person making the request. You could also ask for the other person’s eBay ID so you can communicate directly at the site in which case both parties’ messages will be recorded and allow eBay to investigate your concerns.