So keep in mind that what is patented is in the claims. Here's the first claim from one of the MS patents on the Ribbon UI:

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1. A method for providing functionality from a software application by displaying an improved user interface at a display device, the method comprising:

organizing a plurality of software functionalities according to tasks to be performed by the software application, the tasks being identified textually by user interface tabs;

upon receiving an indication of a selection of a first user interface tab, providing a plurality of selectable controls associated with a first task, each selectable control being presented by a graphic representation and a textual representation;

grouping the plurality of selectable controls into logical groupings of the plurality of selectable controls, wherein each of the logical groupings combine a subset of functionalities associated with the selected first user interface tab;

dynamically adjusting a layout of at least one of the logical groupings to accommodate the user interface, wherein dynamically adjusting the layout of the at least one logical grouping comprises reducing a size of the graphical representation of at least one selectable control within the logical grouping eliminating the textual representation of at least one selectable control associated with the at least one logical grouping, and preserving the graphical representation associated with the at least one selectable control associated with the at least one logical grouping;

upon receiving an indication of a selection of a second user interface tab, providing in the user interface a plurality of additional selectable controls for selecting functionalities organized under a second task associated with the second user interface tab;

after providing in the user interface the plurality of additional selectable controls for selecting functionalities organized under the second task, receiving an indication of a selection of one of the additional selectable controls organized under the second task;

applying functionality associated with the selected additional selectable control to a selected object; and

when the second user interface tab is not selected in the user interface, providing in the user interface the plurality of selectable controls organized under the first task associated with the selected first user interface tab.

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Does this exactly exist in the prior art? You can be sure that Corel looked. That is a, frankly, very narrow claim. It protects a rather well defined implementation, not a general idea of tab-based navigation. This is probably why they were only awarded ~$270k in damages. In patent litigation terms, that's a pittance. It doesn't even come close to paying for their attorneys to work on the case, i.e., MS lost money here. So the courts are definitely recognizing the very narrow nature of what is protected by their patents.

Source: https://www.lens.org/lens/patent/US_8255828_B2

Edit: also keep in mind that wilfulness was found, which means treble damages. I'm a little unclear if the reported $278k number is factoring that in or not, but if it is, that means the actual damages found were 1/3 of that. Which is well into mere nuisance territory for just about any corporation. Heck, that's into efficient infringement territory for Corel, if they think that redesigning would cost more than that (aside from the wilfulness aspect). I guess what I'm getting at here is that this is not something to be up in arms about.

Also, check out what Corel actually did here.[1] That's a pretty obvious clone of MS Word if I ever saw it. Say what you will about patents, but this is egregious copying and I don't think it's wrong of MS to defend themselves here.

1: https://www.techrepublic.com/blog/windows-and-office/review-...