Dispelling a few doubts
OK, a few corrections about the last few paras - although unimportant to this particular article, but important for the overall picture of IBM.
IBM cannot open source AIX. The license comes from the bad old AT&T days, much before Solaris got it from AT&T and that license does not allow IBM to open source AIX. Not that I am sure open-sourcing it is such a good idea. After all, some people want an operating system that has a fixed roadmap - which promises binary compatibility and all that bla-bla. There are other people who don't want all that, and they can well choose linux, which again, IBM supports (IBM has a full fledged team working on all parts of linux) on all of its server lines including z, p, i and x.
Second - yes IBM does stick to its patenting, and files more patents than any other company. In fact, the number two and number three (which includes Hitachi) in the list added up do not file as many patents as IBM. In spite of this, IBM happens to be one of the most active companies to lobby doing away with patents altogether. So IBM's standpoint usually is that they are against patenting, however, as long as patenting exists, and there are others who might sue IBM for patenting, IBM will continue patenting. Of course, most companies these days do not patent to sue other companies, they patent so that they are not sued by some weird startup for inadvertantly violating some patent. Because if you don't patent something, someone else will.
If you have read in the news, IBM recently urged USPTO to allow corporate review of paetnts to reduce their burden, and also improve the quality of patents that get through.