JCM 41: 1959 Pitcher Catcher Batter Back

It is my belief that every card in this set has a matching prize variant, like JCM 29. Card fronts that don't have catalogued prize card backs are listed here. And some cards with listed prize card backs have regular backs here.
Yamauchi

Katsuragi (the guide is missing the full # on the back)

Sakazaki (guide has this as #8657319)

3rd Place Inao - added 4/27/24

2nd Place Bando - added 10/3/24

Fujimoto - added 10/4/24

Fujita - added 10/4/24

Sadaharu Oh (3rd place) - added 10/4/24

Tamiya (3rd place) - added 10/4/24

JCM: Uncatalogued #5

Tenpo - added 10/4/24

Naito - added 10/4/24

Kawakami - added 10/4/24

Sugiura - added 10/4/24

JCM 121: 1950 Baseball & Pennant

7261 Kobayashi - added 10/4/24

JCM 64: 1950 Who Am I?

251x7 Nishizawa - added 7/14/24

1345x71 Fujimoto - added 10/4/24

JRM : Uncatalogued Set

Miyake - added 6/9/24

Fujimoto - added 6/9/24

Ohira - added 6/9/24

Sumoto - added 6/9/24

Bando - added 8/15/24

Masuda - added 8/15/24

Suzue - added 10/4/24

JCM 186: 1949 Blue Border/Batter Back

Fujimura - added 10/4/24

JCM: Uncatalogued #16 - JCM 131? Color Baseball Play?

Similar to the previous set, this looks like the animal back JCM131 series, but featuring a baseball play on the backside. And this set has color fronts.

Ohsawa

Osawa - added 6/22/24

Nakanishi - added 10/4/24

JF 61: 1953 Calbee/Matsuo Green Tint w/Coupon

Takeshi Doigaki - added 5/12/24

Katsumi Shiraishi - added 5/12/24

Shigeru Chiba - added 5/12/24

Fumio Fujimura - added 5/12/24

Saburo Hirai - added 5/12/24

Noboru Aota - added 10/4/24

Yuko Minamimura - added 10/4/24

Tokuji Iida - added 10/4/24

Yuzo Shimada - added 10/4/24

Takehiko Bessho - added 10/4/24

Tetsuharu Kawakami - added 10/4/24