An ébauche is a movement blank — the plates, bridges and going train supplied as a foundation — which the finishing house (the 'manufacture' or brand) then jewelled, regulated, decorated and cased. In its mature twentieth-century form, a small number of ébauche factories (ETA, Fontainemelon, A. Schild, Unitas, Felsa and others) supplied the great majority of Swiss brands.
The system was rational: designing and tooling a calibre is enormously expensive, while finishing and regulating an ébauche to different grades allowed brands to differentiate on quality and price without duplicating the tooling. A single ébauche might appear in a plain market watch and, in a higher grade with better finishing and adjustment, in a respected brand's catalogue.
For the researcher, the consequence is that the dial signature is evidence about retailing, not manufacture. Dating, grade assessment and parts sourcing all depend on identifying the underlying calibre — usually from bridge shapes, setting mechanism layout and stamped calibre numbers — rather than trusting the name on the dial.
The ébauche system also shaped the industry's fate. When the quartz crisis collapsed demand, the ébauche makers were consolidated into what became ETA, and the surviving industry re-emerged with far fewer movement sources. The modern debate about 'in-house' versus 'supplier' movements is the direct descendant of this structure.
Cataloguing practice: record both the dial signature and the movement calibre, and where the calibre is identified, name its actual maker. 'Swiss, retailer-signed dial on an FHF 72 ébauche, c. 1960' is a more useful description than the dial name alone, and it is honest about what is and is not established.