The legal basis for not making unauthorized copies of software and reselling those copies is very, very well established in US copyright law.
The legal basis of other restrictions in a clickwrap license (for instance, authorizing use on only certain types of computers, a la Apple) is a LOT murkier.
Here are some unenforceable (usually) clickwrap restrictions:
* Anything that restricts resale or transfer of legally obtained copies (i.e., first sale doctrine)
* Anything that restricts cleanroom reverse-engineering
* Anything that explicitly disclaims a warranty when it is unlawful to do so (some states require you to provide certain warranties and you cannot clickwrap them away)
Here are things that are largely untested in most jurisdictions with respect to clickwrap licenses [not site license agreements, etc.]:
* Restrictions to only certain types of users (academic/upgrade)
* Restrictions to only certain types of computers (Apple)
The legal basis of other restrictions in a clickwrap license (for instance, authorizing use on only certain types of computers, a la Apple) is a LOT murkier.
Here are some unenforceable (usually) clickwrap restrictions:
* Anything that restricts resale or transfer of legally obtained copies (i.e., first sale doctrine)
* Anything that restricts cleanroom reverse-engineering
* Anything that explicitly disclaims a warranty when it is unlawful to do so (some states require you to provide certain warranties and you cannot clickwrap them away)
Here are things that are largely untested in most jurisdictions with respect to clickwrap licenses [not site license agreements, etc.]:
* Restrictions to only certain types of users (academic/upgrade)
* Restrictions to only certain types of computers (Apple)