When you buy software on CD you are allowed, presumably, to install it on multiple machines. Why should Office 2013 be any different? Like stasys.lukaitis proposed above, if you have multiple machines you need a license for each?! Makes no sense at all and really disenfranchises the M$ userbase. I guess they've never heard of OpenOffice. No wonder the M$ stock price is so low. Their tactics are even lower.