That isn't the tricky bit, generally you have a large organization, it has many moving parts, and general staff turnover. At some point there are parts of the system that "just work" and nobody at the place really knows all the various bits that go into the works. When one of those bits is carrying a license that needs to be paid, negotiated, but you don't know it, it bites you in the backside.
A more common example of this is a hard working engineer who, practicing DRY, finds a perfectly serviceable piece of code on Github which he plugs into the source tree with just a few small changes to hook up the plumbing. Never once checking the license terms. Those things blow up when you get a demand letter from the owner of the code. Most shops though have a license compliance officer type person who is checking for such things.
If it's a core part of your technology strategy, as RBS/ABN say it is, then your legal people need to make sure that you don't accidentally sell it away.
The problem seems to stem(from a ruling last year linked here: https://news.ycombinator.com/item?id=7722956) from the fact that ANB didn't actually specify that the license was staying with it instead of getting sold as a packaged part of one of their subsidiaries.
For a core tech requirement, that's amazingly idiotic, no matter what size organization you're in.
Maybe it's just me, but I'd never even think of doing that. The place I work for has a group responsible for third party licensing and stuff like that. It seems pretty foolish -- maybe even negligent -- to just grab shit off GitHub and stick it in your source tree.
A more common example of this is a hard working engineer who, practicing DRY, finds a perfectly serviceable piece of code on Github which he plugs into the source tree with just a few small changes to hook up the plumbing. Never once checking the license terms. Those things blow up when you get a demand letter from the owner of the code. Most shops though have a license compliance officer type person who is checking for such things.