Oswald is a Lumon employee working in Optics and Design. He works with Burt.

Oswald was referenced by Burt, just once:

Milchick: I have something for you.
Burt: The missing 7199-G. Oswald will be so delighted. I, too, am delighted.

Season 1, Episode 7, Defiant Jazz (12:38)

Nothing else is known about him, but it can be presumed he is involved in the production, distribution, and/or usage of the Ideographic Cards.

7. Defiant Jazz (referenced)

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