V visas are not common today. But there are still people currently holding a V visa inside the United States. The most common scenario involves a child of a legal permanent resident that is now over 21 years old. That child can continue extending his or her V visa while living inside the United States as long as the priority date on their petition is not yet current. In such a case, a person can submit Form I-539 along with a copy of the family petition filed on his or her behalf. The approval will be for a period of 2 years. 8 C.F.R. 214.15(g)(2)("Child of an LPR or derivative child. An [person] admitted to the United States in V-2 or V-3 nonimmigrant status (or whose status in the United States is changed to V-2 or V-3) will be granted a period of admission not to exceed 2 years . . .").
If the priority date on the petition becomes current, USCIS will only extend a V visa one time for a period of 6 months to give the person time to apply for permanent residence in the United States. See 8 C.F.R 214.15(i)-(ii) ("For an otherwise eligible [person] who applies for admission to the United States in a V nonimmigrant category at a designated Port-of-Entry and has a current priority date but does not have a pending immigrant visa abroad or application for adjustment of status in the United States, the Service will admit the [person] for a 6-month period. For such an [person] in the United States who applies for extension of V nonimmigrant status, the Service will grant a one-time extension not to exceed 6 months.").
The regulations set an age out limit of 21 years of age. However, the Ninth Circuit invalidated those age out provisions for V-2 and V-3 visas. Akhtar v. Burzynski, 384. F. 3d 1193, 1202 (CA9 2004). USCIS applied the ruling nationally in this memo. As a result, a person that originally received a V-2 visa before turning 21 years of age, but applies for an extension of the V-2 visa after turning 21 years old, will continue to be eligible to receive an extension of their status by filing Form I-539 until his or her priority date becomes current.