Specializing in IP law almost always requires a bachelor’s degree in science or engineering. I can almost guarantee you that these firms are mostly dealing with biotech and hi-tech companies and that many of their lawyers are patent attorneys with engineering/science undergrad degrees. Also, the $700/hour figure is what the firm bills. The attorneys themselves don’t make anywhere near that although they do earn a very nice living.
The article mentions that an engineering degree is typical for these positions. And you’re right, $700/hr is what the firm bills. My company charges customers about double what I make for my consulting time, so I would figure that a lawyer might see about $350/hr of that $700/hr…which equates to making $700,000/yr if working 40 hour weeks. As you say, a very nice living.