

DC & Marvel PD Comics
I recently ran across listings of Marvel & DC issues that fell through the cracks and didn't have their copyrights renewed. Most don't have super heroes, and few of those that do have any first appearances, but they do give us Marvel monster Fin Fang Foom and Flash villains Gorilla Grodd and the Pied Piper. I'm sure the list is incomplete.
DC PD books:
A Date with Judy - #2, 4-7, 18-79
Adventures of Rex, the Wonder Dog - #1, 31
All-Star Comics - #1-4
Big Book of Fun Comics - #1
Flash Comics - #15-16
Gang Busters - #13
Girls' Love Stories - #9, 13-14
Girls' Romances - #7, 11-12
Jimmy Wakely - #10-16
Leave it to Binky - #45
More Fun Comics - #7-30, 42-44
Movie Comics - #1-6
Movietown's Animal Antics - #24-31
Mutt & Jeff - #1-54, 56
New Adventure Comics - #12-27
New Book of Comics - #1
New Comics - #1-11
New Fun Comics - #1-6
Pat Boone - #4
Real Screen Comics - #22-24
Rip Hunter... Time Master - #1-18
Superman's Christmas Adventure - #1-2
Superman's Girl Friend, Lois Lane - Annual #1
The Brand New Adventures of Rudolph the Red-Nosed Reindeer - Annual #1
The Flash - #106, Annual #1
Wonder Woman - #30-32
World's Finest Comics - #6-8, 35-38
Action Comics Free Souvenir Edition - (1947)
All-American Comics - Ashcan, #1-11, 24-25
All-American Men of War - Ashcan
Double Action Comics - #2
Double Action Comics - Ashcan, #2
Comic Cavalcade "Tomorrow the World!" - #1
Flash Comics Miniature Edition - #1
Make Way for Youth - #1
New York World's Fair Comics - #1-2
Star Spangled War Stories - Ashcan
Superman and the Great Cleveland Fire - #1
Superman Special Edition (Kellog's) - 1954, 1955 1A, 1B, 1C
The Adventures of Superman (Py-Co-Pay) - #1
Marvel PD books:
Journey into Mystery #1-41
Strange Tales #42-44, 85-95