The Shiny Genesect Event was available in Japan and Taiwan and another Shiny Genesect Event is soon to be available in Korea.
It was available to obtain in Japan and Taiwan from the 29th of June 2013 to the 30th of September 2013.
It is available to obtain in Korea starting on the 9th of January 2014 to the 15th of January 2014.
Note: In both Events Genesect is distributed to players that watch M16 (Pokémon the Movie: Genesect and the Legend Awakened.) The only thing that is different about the two Genesect Events is Genesect's ID Number. Genesect's Name and OT are the same in the two Events, they just look different because Japanese and Korean are two completely different languages. For both Events it's Name is "Genesect" and it's OT is "Cinema" in the English Language. Everything else about the two Genesect's are the same such as Moves, Ability, Held Item, Trainer Moto, Nature, Ribbon and Level.
Hope I helped :)