Both formal and provisional designations are overseen by the Minor Planet Center (MPC), a branch of the International Astronomical Union.
[3] The convention for satellites of minor planets, such as the formal designation (87) Sylvia I Romulus for the asteroid moon Romulus, is an extension of the Roman numeral convention that had been used, on and off, for the moons of the planets since Galileo's time.
When the main-belt asteroid 274301 Wikipedia was discovered in August 2008, it was provisionally designated 2008 QH24, before it received a number and was then written as (274301) 2008 QH24.
This practice was soon coupled with the name itself into an official number–name designation, "④ Vesta", as the number of minor planets increased.
[6] The major exception to the convention that the number tracks the order of discovery or determination of orbit is the case of Pluto.