Independent watchmaker
Otsuka Lotec
Also recorded as: Jiro Katayama
Tokyo independent known for industrial-style jump-hour and retrograde wristwatches.
Otsuka Lotec is the brand of the Japanese independent watchmaker Jiro Katayama, who builds watches in very small numbers with machined, industrial-looking cases and unusual displays — jump hours, retrograde minutes and cylinder indicators — inspired by gauges and instruments.
- Country
- Japan
- City / centre
- Tokyo
- Founded
- 2000s
- Status
- Active
- Key people
- Jiro Katayama
Innovations & specialities
- Jump-hour and retrograde displays in hand-built watches
Works by Otsuka Lotec in the catalogue
Open in the catalogue →
Wristwatches · Sold in December 2025
Otsuka Lotec Kai, ref. 5, Sold in December 2025
Antiquorum auction archive, Geneva
Wristwatches · sold in July 2025
Otsuka Lotec wristwatch, ref. 6, sold in July 2025
Antiquorum auction archive, Geneva
Wristwatches · Sold in November 2025
Otsuka Lotec wristwatch, ref. 7.5, Sold in November 2025
Antiquorum auction archive, Geneva
Wristwatches · Sold in January 2026
Otsuka Lotec wristwatch, ref. 6, Sold in January 2026
Antiquorum auction archive, Geneva
Wristwatches · Sold in July 2026
Otsuka Lotec wristwatch, ref. 6, Sold in July 2026
Antiquorum auction archive, Geneva
Linked through the Atlas maker authority list, which reconciles the spellings used by different institutions. Attributions are as stated by each holding institution or auction house.
