Originally Posted by
tdracer
A new STC is a long, complicated process, with countless meetings between Boeing and the FAA. There would be a high level 'Tech Fam' where Boeing described all the changes planned for the MAX relative to the NG, then a series of specialist meetings where the certification basis is negotiated (this somewhat unique for an STC (rather than a new TC) and gets into something called the Change Product Rule or CPR - CPR basically says any system that's changed as part of the new STC has to step up to the latest regulations and be re-certified, but there are exceptions and these are what get negotiated).
The 737 MAX 8 was certificated (as the "737-8") in Revision 58 of the Boeing 737 Type Certificate (A16WE) on 8th March 2017.
While there are indeed a handful of STCs (16 in fact) that are applicable to the MAX 8, they do not form part of the TC.