Is it common knowledge that Clark Kent is an orphan?

[nightwing]

Wasn't there a "Private Life of Clark Kent" Christmas tale where he makes what appears to be an annual delivery of toys, etc to an orphanage...as Clark, not Supes?  I'm thinking the staff at that orphanage knew.

Anyway, it all depends on what you mean by "common knowledge."  Clark didn't go to great lengths to conceal the fact that he was adopted, but he also didn't go around saying, "Hi, I'm Clark Kent.  I was adopted."

More than once I've had friends or coworkers I knew for years before finding out they were adopted.  And you know what?  It didn't change anything when I found out.  So I'd say most Americans don't care one way or the other.  It happens enough that Clark wouldn't draw any attention for it.  (Though for the record, it still doesn't happen enough. More people should adopt!)

I think the only way it could be used against him is if someone already suspected his secret...it'd give them one more piece of the puzzle.  But on its own it means nothing.