Under établissage, a firm bought rough movements — ébauches — from specialist makers, then had them jewelled, escapement-fitted, finished, cased and regulated by other specialists before selling them under its own or a retailer's name.
This made Swiss production flexible. A firm could offer many grades and sizes without owning the machinery for any of them, and could supply retailers who wanted their own signature on the dial.
It also makes attribution difficult. The name on the dial may be a shop, the name on the plate a finisher, and the actual ébauche maker identifiable only from small trademarks, calibre numbers and plate architecture.
Consolidation followed. Through the twentieth century the ébauche trade concentrated into large suppliers, which is why later Swiss watches are often identified by calibre rather than by the firm whose name appears on the dial.
The honest research outcome is frequently partial: 'Swiss bar movement, keyless, cylinder escapement, ébauche maker unidentified' is a complete record, and better than an attribution style alone cannot support.