Lighting and electronics developer Hella says that it provided a comprehensive lighting package for the Audi A8, developed in collaboration with Audi - including the OLED rear lights.

Audi A8 OLED Rearlights photo

The Audi A8 2018 (which is now available) uses four small vertical OLED modules on each side, each with what seems to be 6 different structured panels, a large red one and five yellow ones which form the turn indicators.

We do not know who produced the OLED panels themselves. The 2016 Audi TT used OLED lighting panels produced by OSRAM.

Kyulux - Hyperfluoresence OLED emittersKyulux - Hyperfluoresence OLED emitters