3rd Inversion — Maj7

7th in bass

Prove it — just do the practice exercise.
CMaj7 3rd Inversion
B (7)C (R)E (3)G (5)
In 3rd Inversion the 7th is on the bottom:

• 7 – R – 3 – 5

Sounds bright and open. The 7th resolves naturally downward.

Example: CMaj7/B = B + C + E + G