In 2239, the planet was purchased by a private concern, a gentleman named Mr. Brack. This was later revealed to be one of many aliases of the planet's only inhabitant, Flint the immortal, when the Federation starship USS Enterprise visited in 2269. (TOS: "Requiem for Methuselah")
In 2293, the location of Holberg 917G in the Milky Way Galaxy was labeled in a star chart that was in Captain James T. Kirk's quarters aboard the USS Enterprise-A. (Star Trek VI: The Undiscovered Country, okudagram)
In 2328, this was the destination for passengers traveling from Dallas, Texas, Earth via commercial transport. Amanda Vackrinos, Kevin Ryan, and Paulina Ryan traveled on the SS Kogin. (TNG-R: "Inheritance", okudagram)
According to Star Trek Maps (p. 28, chart D), Holberg 917G was the seventh planet in the system, and had once supported a neanderthaloid population similar to the Kalar. The single moon of the planet seen in the original version of the episode was named Tanisse.