Dominic from the Copyright Blog offers striking examples of how copyright and privacy are similar. On the surface, his quotations missing the word "privacy" can very much be used in the context of both pro-privacy and pro-copyright arguments. He uses this to justify the fact that if you support privacy, it really isn't much a stretch to support copyright. However, I can not ignore that the primary justification he provides for copyright, namely "it advances our culture and our knowledge, it inspires others to create more things, it moves us forward as well as entertaining and delighting people", does not make any sense for privacy rights.
I see similarity with arguments for protecting "intellectual property" without taking into account the differences in what constitutes intellectual property. The rules and philosophy between copyright, patents and trademarks are quite different.
And if you scratch past the surface, privacy rights and copyright are quite different.
Privacy is fundamentally a system to protect you from others who may find your private dealings objectionable. Even if you are perfect, someone out there will want to put you in jail, embarrass you, or threaten you if they figure out enough information about you. This could be copyright enforcers, it could be the DEA, it could be anti-abortion activists. Privacy is a protection of the individual against any kind of (state-sponsored or not) malicious harm to them. It's a check and balance against coercive power.
Copyright does not have any of these privacy attributes. It protects published work which are intended to be in the public sphere. Copyright serves as a profit incentive for publishing work to a public sphere, the goal of which is to generate revenue. This is by selling as much copies of that work as possible, with as much possible cost and government-endorsed scarcity as the market will allow. Copyright may look like privacy at a shallow level, because it's enforcement is to make information scarce or unavailable.
But the purpose behind copyright is different. The purpose of copyright it is not to make information scarce or unavailable, quite the contrary. As Dominic rightfully points out, the theory behind copyright it to use the economic powers scarcity affords to make the continued development of artistic and useful works more economically feasible, to allow new and more diverse creative works to be made available to the public. This is fundamentally different from the idea of privacy!
In fact, they are so different that privacy and copyright are diametrically opposed to one another. In the world of the information age, you have to pick between privacy or copyright. You can not have proper enforcement of both.
The problem with copyright infringement is that copying is typically done in private. Nobody wants to "publish" their legal transgressions, so copyright infringement is one of the most private of acts.
So how are you suppose to even discover copyright infringement? Simply said, you must invade everyone's privacy on a massive scale. If you want to enforce copyright, you have to gain knowledge of people's private dealings. Yes, your Internet usage, your e-mails, your file and program usage behavior on your personal computer are all things that can be used to discover copyright infringement. The problem is, they are not things you have "published" for the world to see. Allowing companies the ability to access, store and data mine this information for various purposes is an invasion of privacy.
But copyright enforcers want this information regardless. Of course you can't not opt-in or opt-out otherwise all the filesharers would opt-out from being monitored. So they want involuntary access to your private information, the purpose thereof so they can punish you for any legal transgressions they find.
To be fair technology companies on the free culture side of things, like Google, want this information too. However Google wants it for different less malicious reasons. In addition, Google doesn't need to personally identify you the way copyright holders or their enforcement apparatuses need to.
So in conclusion, copyright and privacy can not really coexist anymore. Comparisons between copyright and privacy are not so simple, and there needs to be a focus on the differences between the philosophies of privacy and copyright to understand how one can be opposed to the idea of copyright but for the idea of privacy. In fact, you can only really be for one or the other.