Independent workshop (name not established)

Establishment and workshop methods

The unnamed target resolves to Derek Pratt’s independent horological practice in Switzerland, not to a separately evidenced company name. Treffry dates Pratt’s independence to 1972 and places his home workshop at Balm bei Günsberg, Switzerland.

Pratt restored historical timekeepers and made precision mechanisms and engine-turned dials using traditional workshop equipment. 12

Work credited through collaborators

A Collected Man identifies Pratt as Urban Jürgensen’s technical director from 1982 to 2005. His Urban Jürgensen work included perpetual-calendar modules on Frédéric Piguet ébauches; supplier movements were not his complete manufacture.

The Oval tourbillon was Pratt’s design and construction project; Voutilainen completed and finished it, and Affolter supplied later precious-metal cases. Pratt’s Double-Wheel Remontoir Tourbillon entered the 1997 Prix Abraham-Louis Breguet competition.

Pratt assisted George Daniels with components and technical communication; this does not establish Pratt as sole inventor of the co-axial escapement. 21

H4, death and posthumous names

Pratt’s H4 reconstruction used outside case, enamel and engraving specialists; Charles Frodsham completed it in 2014. Pratt died in 2009; posthumous watches carrying his name require separate project attribution.

Luca Soprana’s current Derek Pratt presentation describes a later wristwatch project honoring Pratt; it is not evidence of continuous operation of Pratt’s original atelier. The practice’s significance is its combination of restoration, craft skills and complex mechanisms, much of it credited through other makers’ products. 132