Conversation so far:
Who is Cosmo Kramer based on?
The character of Kramer was originally based on the real-life Kenny Kramer, a neighbor of co-creator Larry David from New York.
Why did co-creator Larry David use Kenny Kramer to base the character of Cosmo Kramer on?
Was Kenny Kramer a friend of co-creator Larry David's?
How were relations between co-creator Larry David and Kenny Kramer?
Larry David was hesitant to use Kenny Kramer's real name because he suspected that Kramer would take advantage of this. David's suspicion turned out to be correct.

Question: Did Kramer agree for his name to be used for the show?
Self-contained rewrite: Did Kenny Kramer agree for his name to be used for the show Seinfeld?