Bob Heer reminds me that in 1988, DC Comics put out a book called The History of the DC Universe and they included an essay by Bob Kane about the creation of Batman. Here's an excerpt from it…
I called in my friend Bill Finger who was a pulp writer just starting out to write for the comic books. He made several suggestions which enhanced my crude Batman sketch. He told me to remove the eye-balls from the slits in the mask to make it appear more sinister looking, and also to bring the eye-mask that I had originally drawn down over his face into a Bat-cowl. After awhile the first innovative Batman sketch was completed.
However, I soon refined his early look by elongating the short ears on the Bat-cowl, scalloping the side of the long gloves and changing the stiff bat wings into a scalloped bat-cape which would billow out behind him when in action to make him appear like a large bat.
I would like to pay homage now to my good crony, Bill Finger, who was truly the unsung hero on the entire Batman mystique. He helped me considerably on the innovative sketches on Batman and became the chief and best writer for most of the Batman series from 1939 to the 1960s. His unique style of story telling created the somber, mysterioso mood of the early stories which prevail once again with the current writers on Batman, removing it from the "campy" style of the Batman TV series. Bill also created many of the bizarre super villains such as the Joker, Scarecrow and Catwoman. I created the Penguin, The Riddler, and we collaborated on other villains along the way.
I regret that I did not give Bill a byline, which he richly deserved, but somehow the policy in those days was to give credit only to the original creator and not to the writers who came in after the fact. Bill, I wish you were around now for me to give your just dues for your invaluable input into Batman. I thank you now and God bless you eternally.
There is some dispute over the creation of the Joker. Jerry Robinson was Bob's main art assistant in those days. In fact, the way a lot of people think Bob Kane drew in the early forties was actually the way Jerry drew. Jerry, who always impressed everyone as a man of great integrity and certainly not a credit grabber, claimed he created the Joker. Bob insisted it was Bill Finger and it may well have been; not that Jerry was fibbing but it's likely he contributed something, Finger contributed something and then different definitions of creatorship are in play here.
In any case, it seems pretty clear Bob Kane did not create the Joker and yet last I looked, his contract with DC said they had to say he did. They have to say Bob created all the Batman mythos, Batman included.
So here's another time Bob admitted Bill Finger deserved a byline — "richly," in fact. Even if "the policy in those days" justified not giving it to him then, what justified not giving it to him in 1988?