Ofmega were based in Sarezzo near Brescia, Italy, and were still in business until recently (and may still be so - but I cannot detect any signs of life).
The origins of the company are much debated. A plausible story is that Ofmega grew out of a company called Officine Mecchaniche Giostra (OMG), Ofmega being the first two letters of the first two words and the first and last letter of the last word. OMG itself appears to be related in some way to the earlier legendary brands ‘Magistroni’ and possibly ‘Gnutti’. On their 2003 web site Ofmega claimed to have in business for over 50 years, so there is probably some truth in the idea that they used other brand names or did sub-contracting work for other brands.
The history of Ofmega’s patents sheds some light on these various stories. In a 1966 patent the company was referred to as ‘OF. ME. GA’, with full stops after the ‘OF’ and ‘ME’. It is not difficult to imagine that ‘OF. ME.’ stands for ‘Officine Mecchaniche’, but ‘GA’ is a bit more obscure. The company is described as being owned by Dino Perotti.
In a 1975 patent the company was clearly identified as Ofmega, and the owners were now listed as Dino and Mario Perotti. This format endures throughout the patent record until it starts to dry up in the 1990s.
Whatever their pre-history might be, Ofmega produced some of the more interesting Italian equipment available in the 1980’s. They also were co-sponsors of major cycling teams (at one time Gianni Bugno rode for the Atala-Ofmega team) and generally had an alarmingly high profile.
Ofmega’s better groupsets were called Premier, Mistral and CX and their less good ones were called Mundial and Master.
The Mistral groupset, with its wacky use of plastics was particularly innovative. Ofmega took the radical step of having the Mistral parts designed by a serious professional industrial designer; Bruno Giardino of Studio Giardino in Turin.
The hoopla surrounding the Mistral groupset should not blind us to the virtues of the Premier components. Ofmega could do quality aluminium as well as space age plastic.
Frank Berto claims that in 1987 Ofmega merged with Simplex. Certainly from about this time Ofmega stopped designing their own derailleurs and started rebadging Simplex models. However Simplex then went on to have a sequence of increasingly disinterested owners, while Ofmega appeared to continue on its own separate course, and to do so until around 2005 - so I am uncertain as to the nature of any merger.