If I am selling software commercially and I offer users free upgrade for 12 months after purchase, can I make them agree to a new licence when they download an upgrade?
What should the original license say in order to stipulate this?
And if I can do this, then wouldn’t it be possible to put in the new license that they are no longer entitled to free upgrades (being the devil’s advocate here)?
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I’m not going to give you legal advice – see a lawyer – they will tell you what you can and cannot write, and they will also write it correctly.
In terms of having them agree to the license, yes, you can have them do that prior to installation and this is entirely normal on some platforms (i.e. Windows) when you install software.
You can modify licenses as need be; services such as iTunes are constantly changing their terms of use, and Office 2013 has a different license to 2010.
The wording of your licensing depends on what you can do. For example, if you say “free upgrades for life” then that forms a binding contract on you; however were you to say “free upgrades for life unless withdrawn earlier” then that is a different story.
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