eBook compiling

As far as I can tell, there’s no way to build an expiration date into an eBook compile, but does anyone have a workaround for this? I need to share pre-publish drafts but don’t want recipients to distribute them.

Wouldn’t this be something that’s controlled by the site where you’re sharing? (Smashwords, Create Space, Amazon, iBooks, or wherever).

That could be, for some sites, but I’ll be sharing it as a download through my own, which doesn’t have a mechanism for controlling accessibility to the eBook once it’s been downloaded.