Piguet was a very common name in the french speaking part of Switzerland, and still is today.
Furthermore, the old Piguet, any of the famous names, had nothing to do with the Blancpain watchmakers who resided in Villeret, close to La-Chaud-de-Fonts, some 120km away from Le Brassus and surrounding villages in the Vallée du Joux, where many famous Piguets are known.
The 2013 book "A Grand Complication: The Race to Build the World's Most Legendary Watch." written by Stacy Perlman describes in detail the many 'Piguet' contributors to the Graves watch. Here is a transcript of p. 184 (names in bold, emphasised by yours truly):
"… Remarkably, given the five centuries that preceded this undertaking, outside of patent design, the construction of complicated movements had never been enshrined in a manual. Traditionally, watchmakers worked from memory, passing on their craft and wisdom to their apprentices.
[…]
Patek Philippe assembled the finest watchmakers in Switzerland to produce the Graves Supercomplication, nearly all members of the country’s most important horological families. the endeavour recalled a time when Europe’s kings called to their court expert scientists and specialist to craft instruments that defined an era. Le Fils de Victorin Piguet in Le Sentier, founded the the late nineteenth century, specialising in the production of complicated watches, blank movements, and dial trains, headed up a great deal of craftsmanship and manufacture. Michel Piguet of Le Brassus designed the grande inner mechanism, and Henri Daniel Piguet built the hand-setting mechanism. The case, built with a depth to accommodate the highly complex movement, was the work of Luc Rochat of L’Abbaye.
Jean Piguet, chief technician on the project, was kept awake at night attempting to the extreme difficulty posed by the setting mechanism. Three pairs of hands - for the mean time, sidereal time, and the alarm - all shared the same winding crown. When, during one of his sleepless nights, Piguet hit upon the solution, the jumped from his bed and immediately wrote it down, terrified that he might forget the answer by morning. His solution: a double winding method - pushing the crown forward wound up the striking method, and turning it backward wound up the watch. Pushing on the left of the pendant set the alarm. Pulling the cowrie out set the mean and sidereal time function…"
As I am currently moving house I do not have all my documentation ready at hand. But it can be said the following:
The closest link between the Piguet watchmakers involved in the Graves watch and the (now merged with Blancpain) Frédéric Piguet ebauche company could be seen in Henri Daniel Piguet, who was a brother to F. Piguet's founder Louis Elysée Piguet. On the other hand, Henri Daniel Piguet was married to a Audemars daughter (from the watch manufacturer) and had a stake in that company. Does this make the Graves watch now also an Audemars Piguet?
So, using Jeff's logic above, one could also rightfully say that it is an in-house movement, as the chief technician was a Patek employee. ;-) Or, that the Breguet No 4377 was a Blancpain (or Audemars Piguet, if you like ;-)) as well, as for example the same Henri Daniel Piguet who contributed to the Graves watch also contributed to completing this watch.
In other words, the landscape than as well as the family genealogies were complicated - just as the watches. Current definitions of in-house vs. outsourced face difficulties to explain the topology of the then watchmaking world.
So, clearly Jeff made an ironical statement but it needs some knowledge to decipher it!
Cheers,
Magnus