the two "superlative" movements of the 20th century, the AP/VC 2003/1003, and the AP/VC 2120/1120, were JLC developments, initiated and funded by AP and VC (and in the second case, by PP as well)
The manual wind ultra thin was itself based upon a L.E. Piguet - Louis-Elysee Piguet - 9 ligne movement, cal. ML, whose rights were owned by AP at the time. (see my comments in another post in this thread) (sorry, I made a typographical error in my original post, and mistakenly typed F. Piguet, which descended from the L.E. and V. Piguet companies and workshops, but are arguably entirely different companies)
Many/most of the base movements, even entire complications, of the "basic" (read: not radical bleeding edge) models from AP and VC during the last half of the 20th century (and a little more sporadically before that, for AP, while just as "intimately" for VC even back to the early 20th C) are based upon JLC movements (the JLC 888/889 the most in terms of volume units used and shipped)
I would just caution that it was a very different world back then (but then, isn't it always?) - be careful not to draw historically inappropriate conclusions from small, individual "facts."
Remember that JLC was at one point part of a Swiss holding company, and for a short time, alongside VC before VC was spun out by Mr. Ketterer (SAPIC, if I remember correctly)
Remember that later, AP financially supported JLC through a significant equity investment into JLC. This fact is both a tribute to the significance of JLC as a movement supplier (AP executives have openly commented that they felt JLC was too important a movement supplier to risk letting it go out of business, strong praise indeed) and a reminder that great technical skills and talent does not always equal commercial success or viability, regardless of whether such was due to market reasons or management reasons.
TM