The ESRB wouldn't let Valve release the cinematic trailer for Left 4 Dead 2, so what did they do? They "leaked" it, obviously
Valve intentionally 'leaked' the cinematic trailer for Left 4 Dead 2 after the Entertainment Software Ratings Board (ESRB) refused to approve its release due to concerns over profanity and violence. Former Valve writer Chet Faliszek revealed the anecdote, explaining that the ESRB's strictness on marketing materials led Valve to release the trailer themselves.
Rock Paper Shotgun
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