The worst part of this is that it's retroactive, so adding a robots.txt that denies the wayback machine access causes the machine to delete all history of the s

The worst part of this is that it's retroactive, so adding a robots.txt that denies the wayback machine access causes the machine to delete all history of the site. This is really annoying for patent cases where the prior art is on the applicant's own website: they can go and remove the prior art so it's no longer available (which is why examiners make copies of the wayback content before making their reports).