User Activity

I have noticed that once signed out out of eBay, that certain previous activities remain visible. Example, I have purchased a hat, paid, then signed out. While the eBay unsigned in page is visible, it shows "You have recently purchased..." with more ...
What is eBay's position to "title of goods" ? That is to say, when are the goods legally a buyers property ? At point of payment, sending or receipt or other.