According to prevalent definition of Ubhayachari Yoga in Vedic astrology; if in a horoscope, there is one or more than one planet in the house prior as well as the house next to the house of placement of Sun, Ubhayachari Yoga is formed in the horoscope. Ubhayachari Yoga may bless the native with good results related to profession, health, money, wealth, prosperity, authority, fame and many other things.
The placement of Moon, Rahu and/or Ketu only, in the house prior or next to the house of placement of Sun is not considered for the formation of this Yoga. Hence one or more than one planet other than Moon, Rahu and Ketu should be placed in the house prior as well as next to the house of placement of Sun in a horoscope, for the formation of this Yoga in that horoscope.
In real practice, Ubhayachari Yoga is not seen producing such results when only the aforementioned conditions are met. Hence more conditions should be met in order for this yoga to be formed effectively in a horoscope. If Sun is functionally benefic in one such horoscope, this yoga may produce better results. If the planet/planets placed in the prior and next house are also benefic; Ubhayachari Yoga may produce even better results.
Taking an example, suppose Sun is placed in the second house of a horoscope in Aries, Venus is placed in the third house in Taurus and Saturn is placed in the first house in Pisces. Sun, Venus and Saturn are all malefic in the horoscope. In this case, Ubhayachari Yoga may not be formed in the horoscope, though the primary conditions are met.
Taking another example, suppose Sun is placed in the second house of a horoscope in Virgo, Mercury is placed in the third house in Libra and Mars is placed in the first house in Leo. In this case, Ubhayachari Yoga may be formed in the horoscope; since Sun, Mars and Mercury are benefic. Hence the native may witness good results related to profession, reputation, finances, health, lifespan, wealth, family and a number of other things.
Once the formation of Ubhayachari Yoga is confirmed in a horoscope, the next factor to check is its strength. The strength of this yoga is calculated through the placements of planets involved in its formation in various signs, nakshatras and navamshas; as well as through the influences of other benefic and malefic planets on them. The overall theme of horoscope and running times (Mahadashas) also affect the strength of this Yoga.
Taking an example, suppose benefic exalted Sun is placed in the tenth house of a horoscope in Aries, in Leo navamsha of Bharani nakshatra. Suppose benefic exalted Venus is placed in the ninth house in Pisces, in Libra navamsha of Uttarabhadrapada nakshatra; and benefic Mars is placed in the eleventh house in Taurus, in Capricorn navamsha of Krittika nakshatra. Sun and Venus are exalted in their respective signs and they are strong in their respective navamshas. Mars may do very well when placed in Capricorn navamsha of Krittika nakshatra. Hence strong Ubhayachari Yoga may be formed in this case.
Looking at the running times; when Mahadashas (planetary periods) of malefic planets are in effect; benefic effects of Ubhayachari Yoga may reduce. When Mahadashas of benefic planets other than the ones involved in the formation of this yoga are in effect; benefic effects of this yoga may increase. When Mahadashas of the planets involved in the formation of Ubhayachari Yoga are in effect; the native may witness maximum benefits through this yoga. For instance; in the recent example, the native may benefit the most during Sun Mahadasha, Mars Mahadasha and Venus Mahadasha.