A 13b9, 3rd inversion (G in the bass)
Also written as A13b9/G.
Notes, from the bass up
G (bass)BbF#AC#E
The same notes as A 13b9 (G, Bb, F#, A, C# and E), rearranged so G is the lowest note. Use it to move between chords with smaller jumps across the keyboard.