Yoop:
From 2008:
"410.42 Exposed Luminaire.
(A) Exposed Conductive Parts. Exposed metal parts shall be connected to an equipment grounding conductor or insulated from the equipment grounding conductor and other conducting surfaces or be inaccessible to unqualified personnel. Lamp tie wires, mounting screws, clips, and decorative bands on glass spaced at least 38 mm (11/2 in.) from lamp terminals shall not be required to be grounded."
As Vin said...metal poles must be bonded.
