D. Koeppel was an Earth Starfleet officer in the 22nd century.
In January of 2155, Koeppel worked in Robotic Systems at the Fleet Operations Center on Earth. Koeppel's office was located in room 4233. (ENT: "Demons" set artwork)
Koeppel's name was seen on directory listings seen on the set of "Demons".
D. Koeppel was named after Enterprise film editor foreman David Koeppel.