I initially didn't want to post here, since this is a topic that I can get extremely argumentative about, but I feel there's some things that really need to be pointed out. Apologies in advance for a rather long post.
The second precept is to refrain from taking what is not given. So to see how this precept affects downloading and uploading copyrighted material (and copyright in general), we should investigate what it is that is given in the case of buying the material.
The obvious answer, that what is given is the actual file itself, is legally incorrect. The file, or more accurately its representation on the disk as a string of 1's and 0's, usually doesn't become your property. After all, if it truly became your property, you would be allowed to copy it, modify it, give it away, whatever you want really. But these rights are usually retained by either the author or some publisher, and doing those things is a crime. Though you receive the file after buying it in an online store like the iTunes store, it does not become yours.
What you're actually given is a use right. In the case of an audio file, it's the right to listen to it. In the case of a movie, it's the right to watch it. These rights are severely restricted too. For example, even though you're usually allowed to watch a movie you bought with friends or family, you're usually not allowed to watch this same movie with co-workers at the workplace.
So when you download copyrighted material, you're taking a use right. When you upload copyrighted material, you're taking a right to redistribute. Both of these rights are abstract entities which the copyright holder has in unlimited supply, and which only they are allowed to give away (though they can license others to do so as well).
With that established, lets explore what this means.
First the download case. Though you are taking the use right, you're not taking what is not given. After all, clearly there's someone giving it. A downloader doesn't sneak into someone's house to get it, they're offered the opportunity to download. I believe others in this thread have already pointed out that this is similar to the case in the monastic code where a groundskeeper of an orchard gives away fruit that was not his to give away, without the bikkhus receiving the fruit committing an offense.
Far more interesting is the case of the uploader, or more generically, the redistributor. It is interesting because the law here leads to situations that few people would recognize as theft, but which would be a break of the second precept anyway if we consider rights as objects that can be taken and given.
Let's start with the basics. Suppose someone uploads a copyrighted movie to a website. What they're taking is the right to distribute and, for each download, the right to watch for the downloader. Both of these can only properly be given by the copyright holder, so the second precept is broken. So far so good, right? But now lets extend that logic.
- Translating a book (or converting it to braille script) and giving it to someone else is copyright infringement, even if said person owns the original. Only the copyright holder may create and distribute a derivative work, so this would be the taking of a non-given right and therefore it breaks the second precept.
- Printing a website creates a copy of a copyrighted work. Only the copyright holder may give one this right, so doing so without permission breaks the second precept.
- Drawing Mickey Mouse and putting the result on your homepage is copyright infringement. Disney owns the image of Mickey Mouse, and they're the only ones allowed to create derivative works and distribute them. Even if you drew this picture yourself it is still illegal, and if we accept that this constitutes the taking of rights that were not given by Disney, this clearly breaks the second precept.
- Public performances are copyright infringement. The use right generally granted when you buy a copyrighted work does not grant the right to use this however you please.
- As I wrote briefly above, watching a legally bought movie at the workplace with your coworkers would be breaking the second precept. After all, you were only given a use right for watching at home, not for a public screening.
- Playing copyrighted music at an office party is breaking the second precept as well for the same reason.
- Reading a children's book aloud in the library for the entertainment of children is also a public performance and thus breaks the second precept.
- Choreography is also covered under copyright law. Suppose that a class wants to perform some dances from High School Musical for their family. If they do, they're breaking the second precept.
- Singing the song 'Happy Birthday' at a restaurant would also break the second precept. The lyrics and melody of this song are copyrighted by Warner Music Group (http://en.wikipedia.org/wiki/Happy_Birt ... ght_status" onclick="window.open(this.href);return false;), and unless you obtain a license from them, a public performance would be taking this license without it being given.
All these cases, both those generally seen as piracy and those that aren't, have in common that they involve a right being taken without being given. That which would make downloading a break of the second precept would make all of them a break of the second precept.
Now, I have a big problem with this. If we say that the above indeed breaks the second precept, not only do we stretch the definition of stealing to the point of it being unrecognizable, we also say that what is and is not covered by this precept can be changed. It means that the word of the Buddha and the precepts can be superseded by the demands of the likes of Disney Corporation and Time Warner. Let's not forget that copyright did not exist before the 18th century, and has changed a lot since then, often under corporate pressure. Inevitably there'll be new laws in the future too, turning an ever-increasing amount of abstract objects into property. Will the second precept change accordingly? Furthermore, since property laws are different in different countries, does that mean there are actions that would break the second precept in one country, but not in another?
In my opinion, 'taking what is not given' can not refer to something abstract like a right. And by extension, I don't think that the second precept covers copyright infringement.
That is not to say that copyright infringement can't be unskillful. But in fact, lots of things not covered by the precepts are unskillful. Punching someone in the face is unskillful, but unless the punch kills someone, none of the 5 precepts are against it. Calling someone harsh names is unskillful, but unless a lie is spoken, none of the 5 precepts covers this. Copyright infringement can in fact hurt. Calling it theft though is ridiculous.