SMH (“Société de Microélectronique et d ' Horlogerie SA”) was the name for a group of Swiss watch manufacturers formed by the merger of ASUAG and SSIH. Now known as Swatch Group, it is the world's largest watch group, which now includes many other manufacturers.

• May 26, 1983 - At a press conference, the merger of ASUAG and SSIH is announced. The resulting entity, tentatively called ASUAG-SSIH, would become SMH two years later.
• 1984 - Swatch SA founded
• 1985 - “ASUAG-SSIH Group” renamed “SMH”
• 1987 - All subsidiaries of Ebauches SA are reorganized under ETA
• 1988 - SMH divests its stake in France Ebauches
• 1991 - Balmain, conceived in 1987, is launched co-located with Longines
• 1991 - SMH takes over Porta Micromechanic AG (PUW and Rowi) as well as VEB Uhrenwerke Ruhla
• July, 1992 - Blancpain and Frédéric Piguet acquired