As mentioned by others, the company was really Caldera Linux (later to rename themselves "The SCO Group"), who were one of the original business LInux distros. They bought SCO's unix division with the intention of using SCO's sales channels to sell Linux to an existing customer base. This was during the dot-com boom, when Linux related shares went sky high. Just prior to that, SCO had been looking at buying a Linux distro company to follow that strategy themselves, but they waited too long and missed their opportunity before the share prices went against them.
In general it was a very good plan. However, Caldera's customer service was not exactly the best. You can get away with that in the proprietary world, but in the Linux market there's too much competition and customers can switch suppliers too easily (which is why customers like Linux). The "sue world + dog strategy" came about when McBride was brought in.
SCO (the real SCO, not SCOG) had a joint venture with IBM to develop a common Unix system which would cover the market from small to large systems. If I recall correctly, it was called project Monterey (or something like that). IBM was supposed to work on the large systems, while SCO was supposed to provide the x86 expertise.
However, when SCO sold their unix division to Caldera and became Tarantella, IBM looked at the way the market was going and exercised their right to pull out of the partnership. The original partnership agreement let them do that if there was a change of control in SCO. IBM realized at that point that Linux was going to take over the market and that the proprietary unixes were doomed, at least on commodity hardware. IBM then put their sales efforts behind promoting Linux on IBM hardware and backed by IBM services. Linux gave customers what they had always wanted from unix but never really had - a truly vendor independent operating system. The proprietary unix market was fragmented, while using Microsoft Windows NT was just trading one proprietary vendor for another.
One of the several SCOG lawsuits against IBM was relating to the termination of project Monterey. It's hard to say if there is anything to be found there, but if there is, it hasn't shown up so far.
SCOG's copyright based lawsuits suffered from not being able to show any basis for their claims. There was code copied the other way, which made for some amusing times when someone noticed his code being claimed by SCO as one of their crown jewels.