A Brief History of the Marque
In Caluso, north of Turin in the Aosta region, Ottolenghi & Actis built motorcycles using engines from, most likely, Piazza or Ladetto & Blatto, of 173cc and in 1930 they also used larger JAP engines.
The business was renamed Umberto Ottolenghi Motocicli.
Production ended in 1932.
Umberto Ottolenghi designed a series of OHV V-twins for Moto Rumi. The prototypes looked very promising when revealed in 1960 but Rumi had financial woes so they did not enter production.
Sources: MC Storico Conti, Henshaw, Wikipedia.nl