I recently got a mole biopsied and there's pigment left after the shave biopsy. Is it normal to have pigment left over? (photo)

This is typical. This can be removed with laser, radiowave or shave. I recommend following up with your cosmetic dermatologist. Best, Dr. Emer

Yes.  Dermatologists often sample the mole using the shave biopsy technique.  During this procedure the portion of the mole above the skin surface is removed and tested.  Pigment cells often go deeper than the surface and can repigment the skin after this incomplete removal technique.  The rule of thumb is that if the top of the mole is benign, recurrent pigment after shave removal is considered benign as well.  If you are desiring a more "permanent" fix, excision and suture is a complete removal.  Hope this helps.