Сижу, читаю: "Registration is required for
Foreigners visiting India on long term (more than 180 days)
Student visa(S) (including those coming for study of Yoga, Vedic Culture, Indian system of dance and Music),
Research Visa(R),
Employment Visa(E),
Missionary Visa (M) ,
Medical Visa(M) or
Medical Attendant (MX) Visa are required to get themselves registered with concerned FRRO/FRO within 14 days of his/her first arrival, irrespective of the duration of their stay.
If the Indian Visa has a stipulation/ observation/ Special endorsement made by Indian mission/ Embassy on the Indian Visa for Registration, the Foreigners are required to be registered..
Foreigners visiting India on other categories of long term visa including Business/Entry(X) visa would not require registration with the concerned FRROs/FROs ,if duration of his/her stay does not exceed 180 days on a single visit. In case a foreigner intends to stay for more than 180 days on a single visit he should get himself registered well before the expiry of 180 days."
http://immigrationindia.nic.in/reg_req2.htmВ общем, с бизнес визой можно не регистрироваться, если одновременное пребывание не превышает 180 дней.