Re:Why are the Microsoft Office file formats so complicated?...
by makomk on Monday September 12, 2016 @05:15AM
(#12478206)
Worse, it's designed in a way that works completely differently from every other XML office format to allow Microsoft to patent it. Doing document markup the normal way in XML has too much prior art to be patentable (though that didn't stop Microsoft from trying), but they managed to get a patent on their oddball way of doing things.
https://en.wikipedia.org/wiki/Comparison_of_Office_Open_XML_...
https://en.wikipedia.org/wiki/Standardization_of_Office_Open...