Yes, DEED is a Scrabble word!

Letter values in Scrabble US: D 2, E 1, E 1, D 2.

Is it a valid word?

DEED is a valid word in the official Scrabble dictionary (US), the UK Scrabble Dictionary and Words with Friends (ENABLE).

a legal document signed and sealed and delivered to effect a transfer of property and to show the legal right to possess it
something that people do or cause to happen

Also: deed of conveyance, human action, human activity.