A New York Times article (February 28, 2011) describes a move by HarperCollins to limit the number of times an ebook at a library can be issued to customers to 26.   Once this limit is reached, the ebook has to be purchased again.  Intuitively, physical books that are borrowed several times face wear and tear and potential replacement, but ebooks face no such deterioration.  Is it reasonable for publishers to limit the number of times ebooks are issued to level the playing field between ebooks and physical books ? As an alternative, would publishers be better off issuing new versions of ebooks that will require a new purchase because of additional content ? Finally, could ebooks be sold as a time limited content to libraries as an alternative model ?