Company

Seibu Lions Co., Ltd.

Seibu Lions Co., Ltd. (Toshima, Tokyo; Personal services and entertainment) appears in 2 related cybersecurity incidents. 1 was a precautionary service shutdown. The latest was disclosed on 2026-11-06.

Profile

Industry/type

Personal services and entertainment

Location

Tokyo, Toshima

Services

Lions Match Bulletin

Website

https://www.seibulions.jp/

Public figures

–

Metric	Value	Scope	As of	Source
–

Incident history

Disclosed 2026-11-06Updated 2026-11-06Fukuoka, Hokkaido, Miyagi, Osaka, Tokyo[Investigating][Severity: Moderate][Precautionary halt][Minor]
PLM: Marines website breach leaks 37,070 nicknames and 11,875 email addresses
[Intrusion][Data leak][Service outage][Site defacement]Leaked 37.1KOrganizations 7
Disclosed 2026-10-29Updated 2026-11-07 17:00Aichi, Akita, Chiba, Fukui, Fukuoka, Fukushima, Gifu, Gunma, Hokkaido, Hyogo, Ibaraki, Iwate, Kagawa, Kagoshima, Kanagawa, Kochi, Kyoto, Mie, Miyagi, Miyazaki, Nagano, Nagasaki, Niigata, Okayama, Okinawa, Osaka, Saga, Saitama, Shiga, Shizuoka, Tochigi, Tokushima, Tokyo, Toyama, Wakayama, Yamagata, Yamaguchi, Yamanashi[Investigating][Severity: Critical][Through a supplier][Major]
Arara: 81,329,467 email addresses leaked or at risk, affecting up to about 380 clients
[Web app exploit][Data leak][Service outage]Leaked 81.3MOrganizations 380

		Incident	Role	Impact level				Methods	Impacts		Status
2026-11-06	2026-11-06	PLM: Marines website breach leaks 37,070 nicknames and 11,875 email addresses	[Precautionary halt]	[Minor]	[Moderate]	7 Chiba Lotte Marines Co., Ltd., Pacific League Marketing Corporation, Fukuoka SoftBank Hawks Corp., Hokkaido Nippon-Ham Fighters Co., Ltd., Orix Baseball Club Co., Ltd., Rakuten Baseball, Inc., Seibu Lions Co., Ltd.	Fukuoka, Hokkaido, Miyagi, Osaka, Tokyo	[Intrusion]	[Data leak][Service outage][Site defacement]	37,070	[Investigating]
2026-10-29	2026-11-07 17:00	Arara: 81,329,467 email addresses leaked or at risk, affecting up to about 380 clients	[Through a supplier]	[Major]	[Critical]	380 Sumitomo Mitsui Banking Corporation, Internet Initiative Japan Inc., Mitsui Fudosan Co., Ltd., Mos Food Services, Inc., Yamanashi Prefecture, AIRDO Co., Ltd., Arara Inc., Asoview Inc., Avance System Co., Ltd., Axel Entermedia Inc., Belc Co., Ltd., Camel Coffee Co., Ltd., Chobirich Inc., DATA X, Inc., Duskin Co., Ltd., GMO MAKESHOP Co., Ltd., GMO Payment Service Inc., Hokuriku Electric Power Company, HR Solutions, Inventit, Japan Leisure Channel Co., Ltd., Java Corporation, Jupiter Golf Network Co., Ltd., Kakaku.com, Inc., Kintetsu Miyako Hotels Inc., Life Corporation, Maker's Shirt Kamakura, Martial Arts Legal Professional Corporation, Matsui Securities Co., Ltd., Monteroza Co., Ltd., NTT TownPage, ODK Solutions, Sakai City, Sasebo City, Seijo Ishii Co., Ltd., Shochiku Multiplex Theatres Inc., Solaseed Air Inc., St. Cousair Co., Ltd., Sumitomo Realty & Development Co., Ltd., Takii, TKC Corporation, U Co-op, Workman Co., Ltd., Zaif Inc., Ministry of Internal Affairs and Communications, Tokyo Metropolitan Police Department, City of Sendai, City of Yokohama, Fujitsu Limited, Fukuoka City, JTB Corp., Kawasaki City, Kyoto City, Kyushu Railway Company, Miyazaki Prefecture, Okayama Prefecture, Okinawa Prefectural Government, Osaka City, Osaka Prefectural Government, Osaka Prefectural Police, Saitama Prefecture, Shiga Prefecture, Suzuki Motor Corporation, Yamaguchi Prefecture, Akita Prefecture, Daito City, Edogawa City, Fuji Television Network, Inc., Fukui Prefecture, Fukushima City, Himeji City, Human Academy Co., Ltd., Isahaya City, Isesaki City, Iwata City, The Kagoshima Bank, Ltd., Karatsu City, Kariya City, Kinko's Japan Co., Ltd., Koriyama City, Kumagaya City, Marugame City, Matsudo City, Miyazaki City, Naha City, Nasushiobara City, Nishinomiya City, Odawara City, Okazaki City, Otsu City, Shimonoseki City, Suzuka City, Takatsuki City, Toda City, Toyama Prefectural Government, Toyohashi City, Utsunomiya City, Yao City, ADS LLC, Aikawa Town, AKASE GROUP Co., Ltd., Akita City, Akita Furusato Mura Co., Ltd., Albait Times Co., Ltd., Asahi Mutual Life Insurance Company, Aya Town, Bank of the Ryukyus, Limited, Barnes de Stroes Japan Limited, Bean Stalk Snow Co., Ltd., BEENOS Entertainment Inc., Bic Camera Inc., BOATRACE Promotion Association, The Chiba Kogyo Bank, Ltd., Chiba Lotte Marines Co., Ltd., Co-op Aichi, Co-op Gifu, Co-op Mie, Congrès Inc., Cosmo Energy Holdings Co., Ltd., CYBIRD Co., Ltd., Densan Co., Ltd., DH Inc., e-CHANNEL Co., Ltd., Echizen Mikuni Boat Race Authority, Ekitan & Co., Ltd., Euglena Co., Ltd., EVENTIFY Inc., Fanplus, Finnovalley Inc., Fire Equipment and Safety Center of Japan, Fujiidera City, Fujinomiya City, Fukui Shimbun Co., Ltd., Fukuoka Chikagai Kaihatsu Co., Ltd., Fukuoka SoftBank Hawks Corp., Fussa City, Gakken Holdings, Giftpad Inc., GMO Epsilon, Gold Flag Co., Ltd., Granvista Hotels & Resorts, Grateful Mind Corporation, Hakone Town, Hamanako Boat Race Authority, Hanamaki City, Hasegawa Co., Ltd., Higashikurume City, Higashimurayama Regional Promotion Organization, Hinode Publishing Co., Ltd., Hirano Masakichi Art Foundation, Hokkaido Nippon-Ham Fighters Co., Ltd., Honjo City, Human Resocia, ILL, Itako City, Itami City, its communications Inc., Iwaki City, Iwamizawa City, Iwate Prefectural University, Japan Digital Laboratory, Joseikan Co., Ltd., The Juhachi-Shinwa Bank, Ltd., Kagoshima Shinkin Bank, Kagoshima Sogo Shinkin Bank, Kainan City, Kaisei Town, Kameyama City, Kanagawa Municipal Information System Association, Kanegasaki Town, Kasama City, Kashiwazaki City, Kintetsu Real Estate Co., Ltd., Kitamoto City, Kiyosu City, Kobe Shimbun Inc., Kotsu Shimbunsha, Kracie Pharmaceutical, Ltd., Kurihara City, Lee Mills & Company Co., Ltd., LightUp Shopping Club Inc., M.STAGE Co., Ltd., M.STAGE Management Solutions Co., Ltd., Manazuru Town, Matsuda Town, Medicus Shuppan, Publishers Co., Ltd., Mibu Town, The Minami-Nippon Bank, Ltd., Minkabu The Infonoid, Misato Town (Saitama), Miyoshi Town, Moka City, Motegi Town, Musashimurayama City, Nagakute City, Naka City, Nakai Town, Naruto City, Natural Island Co., Ltd., Natural Science Co., Ltd., Nihon Fukushi University, Ninomiya Town, Nishio City, Nishitetsu Hotels Co., Ltd., Nishitokyo City, Nishiwaki City, Nyuzen Town, Obanazawa City, Odakyu Travel Inc., Officemotion Co., Ltd., Oga Aquarium Co., Ltd., Ohtawara City, Oi Town, Oiso Town, Okayama Prefectural Industrial Promotion Foundation, Okinawa Churashima Foundation, Ome City, Osaka Gas Co., Ltd., Pacific League Marketing Corporation, Paris Miki Asset Management Co., Ltd., Rakuten Baseball, Inc., Rakuten Securities, Inc., Ryobi Holdings Co., Ltd., Saitama Parks and Greenery Association, Saito City, Sakai Chamber of Commerce and Industry, Samantha Thavasa Japan Limited, Sanjo City, Sano City, Seibu Lions Co., Ltd., Setagaya Shopping District Promotion Association Federation, Shimotsuke city, Shioya Town, Sodegaura City, Sofmap Co., Ltd., Taka Town, Takanezawa town, Takeda Printing Co., Ltd., Tama Shinkin Bank, Ticketplus, Inc., The Tochigi Bank, Ltd., Toho Cash and Carry, Tomakomai City, Toyoake City, Tribeck Inc., Tsu City, Tsunagu Group Holdings, Ueda City, Ushiku City, Vendome Yamada Co., Ltd., VOLZ, Inc., WATAMI FAST CASUAL MANAGEMENT Co., Ltd., WingArc NEX Inc., Yaita City, The Yokohama Rubber Co., Ltd., Yokoshibahikari Town, Yugawara Town, Nagareyama City, Niigata City, AUTHENTIC JAPAN Co., Ltd., ELECOM Co., Ltd., Japan Post Co., Ltd., Japan Society of Civil Engineers, Kojima Co., Ltd., The Nikkan Kogyo Shimbun, Ltd., Shiki City, Tokyo Kantei, Umanity Inc., Warehouse TERRADA, Will Co., Ltd., Kawaguchi City, Itabashi Shopping Street Promotion Association Federation, JERA Co., Inc., Maniwa City	Aichi, Akita, Chiba, Fukui, Fukuoka, Fukushima, Gifu, Gunma, Hokkaido, Hyogo, Ibaraki, Iwate, Kagawa, Kagoshima, Kanagawa, Kochi, Kyoto, Mie, Miyagi, Miyazaki, Nagano, Nagasaki, Niigata, Okayama, Okinawa, Osaka, Saga, Saitama, Shiga, Shizuoka, Tochigi, Tokushima, Tokyo, Toyama, Wakayama, Yamagata, Yamaguchi, Yamanashi	[Web app exploit]	[Data leak][Service outage]	81,329,467	[Investigating]