Good reading here about the early history of Seiko company, subsidiaries and brands.

https://www.beyondthedial.com/post/seiko-history-daini-suwa-fact-and-fiction/

 

Very good article dispelling myths

 

Thank you for sharing this. It is worth reading.

 

This article implies Daini’s Caliber 54 was developed in-house (yet another myth?) but the architecture of the 54/Cronos appears to be a clone of an FHF.

Seiko 54/Cronos (from beyondthedial.com):


FHF 72 (from 17jewels.info):

 

Nope, they are saying - Suwa’s Marvel calibre was truly in-house (1956, probably first Seiko in-house?), while Dani has been using ETA clones till 1960.

 

thanks for the enlightenment by sharing this article. was a very good read about their history!

 

i don’t see it. The bridge is similar, but there are not that many differences between movements in that category.

there are only so many gear train options.

 

And to visualize things - an overview of Seiko Group from "A Journey in Time, the Remarkable Story of Seiko" book. Published by Seiko Watch Corporation@2003