In the summer of 1940, the Leader Novelty Candy Co. released a 36-card set affixed to the backs of Superman Candy & Surprise toy boxes. The red box panels are the first Superman trading cards to be released, preceding the Superman Gum series from Bowman's Gum, Inc. The American Card Catalog reference is R146.

The perforated box panels are approximately 2.375 x 3 inches, smaller than a standard trading card. Counter displays contain 80 boxes. The box art uses the telescoping logo from the cover of Superman #1 (Summer 1939). The Superman logo was later refined by Ira Schnapp around June 1940. The Joe Shuster image of Superman breaking chains is from the back cover of Superman #1.

Each one-cent box detaches into a picture card and a "Valuable Superman Premium Coupon." The coupons could be exchanged for a premium Superman ring, a copy of Superman, membership in the Supermen of America Club, and a Supermen of America felt patch. The "Leader" emblem was available for 10 premium coupons and 10 cents, or free for 50 coupons.

All images for cards #1–24 were published in Superman #5, on sale May 10, 1940. Card #16 also appears in the frontispiece for Superman #7 (November-December 1940). The comic book stories written by Jerry Siegel were changed for the card series. The author of the card text is unconfirmed. The artwork was produced by the early Joe Shuster Shop with Paul Cassidy handling much of the workload. Superman #5 features the debut of artist Wayne Boring on the series. Boring began as a Shuster ghost by mail in 1938 and contributed to Superman features in Action Comics throughout 1939.

Illustrations used for cards #1–24 were also printed in The Adventures of Superman board game by Milton Bradley and the Superman Paint Set from American Toy Works. Five of the panels appear on display boxes of Superman in Movie Style, a series of Ciné Vue film strips released by Acme Plastics.

The last twelve cards received a shorter print run. Cards #25–36 feature art and text that later appeared in the Superman Gum series illustrated by Fred Ray. The story text used for card #33 contains the first appearance of the name spelled as "Kal-el" [sic]. The same image and text was printed on card #1 in the Superman Gum set.

Comic book advertisements for Superman Gum appeared in Superman #8, on sale November 8, 1940, and Action Comics #32, on sale November 22, 1940. The Superman premium prize brochure from Gum, Inc. is dated November 1940. Leader Novelty was originally listed was an official sponsor of Macy's "Superman Adventure", but the company logo was removed from the letterhead by November 26.

Examples have been observed with blank backs or with numbering and text printed on the inside flap. Some panels are printed in black, blue, and red ink; others are only black and red. Early printings of cards #1–24 contain text on the back that is vertically oriented. The text uses the same font as the Superman Gum series. Vertical variations exist with and without branding from Superman, Inc.

Other printings contain horizontally oriented text with the Superman, Inc. chains logo. The layout, branding, and font is the same as the Superman Junior Defense League bread cards and Superman Paint Set. The reverse of some cards state, "This is one of a series of 48 exciting adventures of Superman," but only 36 different cards were released.

Leader Novelty Candy Co., Inc. was chartered in Brooklyn by William M. Freedman in April 1921. The company would later do business as Leader Candies, Inc. and Kastin's Candy. The first known card set distributed by Leader Novelty is a rare Baseball Stars series from 1929.

The image of Superman is reversed on the counter display box.

The history of Leader Novelty Candy, Co. includes legal troubles. In 1924, the Boy Scouts of America listed Leader's "Scout Leader" candy for unauthorized use of a Boy Scout title. In 1936, the Federal Trade Commission brought charges against Leader Novelty for "unfair methods of competition in commerce." The court decision states that the company misrepresented itself as a candy manufacturer in order to deceive dealers. Leader controlled "business stationary, billheads, invoices, catalogues, labels, and other trade literature."

From the 1940s to the 1960s, the Connecticut Agricultural Experiment Station conducted multiple studies that found products from Leader were misbranded. In 1944, federal injunction proceedings were brought against Leader, Novel Package Corporation, and ten other Brooklyn candy concerns. Complaints included gouging the consumer, lowering the quality of candy, failing to keep proper financial records, and unsanitary manufacturing conditions. The Office of Public Affairs reported that candy molds from established firms were altered and rebranded as a more expensive product. Some candy products were being manufactured alongside straw brooms in an open loft. OPA investigators witnessed perspiring workers stirring candy mixture by hand.

On November 15, 1971, Leader was charged by the Eastern District of Michigan for shipping candies that "contained dirt, human hair, and rodent filth." In 1974, company officials were fined $500 by the U.S. District Court of Brooklyn "for manufacturing candy under insanitary conditions and shipping adulterated candy in interstate commerce." The Boy Scouts were again involved after receiving a contaminated batch of candy.

After 82 years of operation, Leader and Kastin's were purchased by Sherwood Brands and "dissolved" on June 25, 2003.