Q: I am taking private music lessons.  My teacher and I agreed that learning to use Logic Pro X will be helpful to my progress.  If he buys a copy, do I have to buy a second copy in order to use it?  Or can we both use it based on purchase?

First, thank you for your thoughtful and quick response.  However, your response seems to confirm my reading of the license agreement that I do not need my own licensed copy of the software.

Secondly, I apologize for not specifically noting that I am talking about running Logic Pro X on a MacAir. 

Thirdly, as I read the license agreement, and as you interpret it, if Person A purchases Logic Pro X, and chooses to allow Person B's computer to be one of her five authorized computers to access iTunes/Mac App Store content, then it is not a violation of the license for both Person A and Person B to use Logic Pro X, plus any other content that Person A has or will purchase. 

I do not want to commit piracy, of course, but as long as Person A does not violate the five authorized computer limitation and does not levy a charge on Person B for allowing his computer to be one of the five authorized (which would mean Person A is reselling the software, music, podcasts, etc.), I do not understand why Person A allowing Person B to use Logic Pro X is piracy any more than Person A allowing Person B to access iTunes Music. Obviously, if Person A deauthorizes the computer owned by Person B, then Person B can no longer use Logic Pro or listen to or use any other content that Person A has purchased from iTunes.

So if my teacher 1) only permits me, among all of her students, to have a computer that she will authorize, 2) has not reached the five computer authorization limit, and 3) does not charge me for listening to her purchased music or using her apps, including Logic Pro X (my lesson fee will be the same with or without her decision to authorize my computer), then I do not see that as piracy.  In fact, it seems content sharing is explicitly permitted by Apple, as long as it is limited to five authorized computers.  As for updates, she would apply them to her licensed computer on her MacAir and then authorize the update on my MacAir.

If a teacher tried to authorize more than five computers (which the system does not allow one to do) and/or charged students for using his/her purchased content, that is piracy.

Am I missing something?