How was that code derived? Does it get its form from copyrighted code Sony owns the rights to? If so I believe it should enjoy copyright protection.
We're seeing a nearly chaotic upheaval in how business is done in modern times, largely because technology is progressing so fast. This can confuse many of the issues at hand. However, I think it can help to view things using older more well understood models. For example, let's look at books. Harry Potter is a copyright protected work which appears to have given much value to both readers and author/rights holders alike. Each page of that book enjoys copyright protection; tearing out a page and adding words, making other adjustments etc., then posting the revised product online would violate copyright. If we can see the logic to that then I think it can help us to gain perspective when reflecting on the Sony incident.
The private key was derived mathematically from the public key material because Sony generated its keys wrong. Copyright has nothing to do with it.
There's a good explanation on YouTube (until they're taken down by the gestapo) which is the Fail0verflow team describing their research. They have a section at the beginning describing the history of console hacking and game piracy, or at least their perspective on it. They take pains to point out that most of their research is not even particularly necessary to pirate games but instead to run user-supplied software on the PS3.
http://www.youtube.com/watch?v=HEFMAP0mTvY
Incidentally, Sony had previously been sued by Certicom for allegedly infringing on patents related to its use of elliptic-curve cryptography.
To the point with Harry Potter: you can think of a continuum of infringement. If you tear a page out and copy it, you will violate the copyright. If you reuse characters or scenes and use them to create your own work, you are making derived works (JK put her stamp of approval on non-commercial fan fiction by the way). But the farther you get away from the original characters the less you can call it infringement. As the link between the two works becomes more and more abstract and less concrete, the new work is more protected. At some nebulous point it is no longer infringing.
For instance, Harry's story and appearance is superficially similar to an earlier work called The Books of Magic, a comic series by Neil Gaiman. You can read his take on it here:
Essentially he throws up his hands and says "borrowing is a fact of life in genre fiction. Deal with it, I did."
How does this apply to computer code? Well, the farther away you get from the original copyrighted code, the less infringing it is. There are extremely limited protections for derived works that amount to Person B having a copy of Person A's code in front of them and editing it.
What those Touretzky pages from CMU show is that there is no such thing as a continuum from computer code to an uncopyrightable abstraction. It is abstraction, mathematics, numbers all the way down. In fact, it is speech that is protected by the First Amendment and suppressing it is a constitutional issue with narrow exceptions.
So no, you can't use a book model for code. It is not the same thing at all. Executable ideas, math, algorithms, just don't exist in the fiction publishing industry.
We're seeing a nearly chaotic upheaval in how business is done in modern times, largely because technology is progressing so fast. This can confuse many of the issues at hand. However, I think it can help to view things using older more well understood models. For example, let's look at books. Harry Potter is a copyright protected work which appears to have given much value to both readers and author/rights holders alike. Each page of that book enjoys copyright protection; tearing out a page and adding words, making other adjustments etc., then posting the revised product online would violate copyright. If we can see the logic to that then I think it can help us to gain perspective when reflecting on the Sony incident.