Who has been buying Caster Co.Ltd. stock?

13 distinct investors have filed 20 disclosed large-shareholding filings in Caster Co.Ltd. (9331), most recently on 2025-12-12. Each filer, their role, the number of shares and the price at filing are listed in the table on this page.

How many insider filings does Caster Co.Ltd. have?

Caster Co.Ltd. has 20 buy-side and 7 sell-side disclosures on record, covering ¥2.8B ($18.1M) in total reported value, spanning 2023-10-10 to 2025-12-12.

Where does StockDrifts get Caster Co.Ltd. insider data?

From EDINET large-shareholding (5%+) reports — the official filing system run by the Financial Services Agency (Japan). StockDrifts parses each disclosure and matches it to daily price history; the original filings remain available directly from EDINET.

Do insider buys in Japanese stocks predict returns?

Not uniformly. StockDrifts scored 101,000+ Japanese large-shareholding filings on fixed 12-month forward returns and found the predictive power concentrated in specific filer types and filing patterns rather than spread evenly across all disclosures.

Caster Co.Ltd. 9331

Company

株式会社キャスターCaster Co.Ltd.

Investors

Buys

Total Value

¥2.8B ($18.1M)

Avg Return

-56.86%

Last Filing

2025-12-12

Caster Co.Ltd. (9331) has 20 disclosed large-shareholding filings and 7 disclosed disposals on record, filed by 13 distinct investors. Together those filings cover ¥2.8B ($18.1M) in reported transaction value. The earliest filing StockDrifts holds for Caster Co.Ltd. is dated 2023-10-10; the most recent is 2025-12-12. All of it is parsed from EDINET large-shareholding (5%+) reports, the official disclosure system operated by the Financial Services Agency (Japan). Across these filings the average return since disclosure is -56.86%, measured from each filing date to the latest available close.

Price & insider activity (12 months)

Recent filings

Date	Type	Source	Insider	Purpose	Shares	Price at filing	Return	Value
2026-06-03	BUY	Market Buy	株式会社Wiz 代表取締役山﨑俊 Wiz Co.,Ltd.	passive	166.5K	¥1,149	-34.2%	¥26M ($166K)
2026-06-03	BUY	Market Buy	株式会社Wiz 代表取締役山﨑俊 Wiz Co.,Ltd.	passive	166.5K	¥1,149	-34.2%	¥26M ($166K)
2025-12-12	BUY	Market Buy	株式会社Wiz 代表取締役山﨑俊 Wiz Co.,Ltd.	passive	144.1K	¥798	-12.8%	¥16M ($106K)
2025-11-14	BUY	Market Buy	株式会社Wiz 代表取締役山﨑俊 Wiz Co.,Ltd.	passive	123.5K	¥824	-15.5%	¥19M ($121K)
2025-04-11	BUY	Market Buy	株式会社Wiz Wiz Co.,Ltd.	passive	100.8K	¥898	-22.5%	¥91M ($584K)
2024-04-15	SELL	Market Buy	ウィルファンドツーエルピー(WiL Fund II L.P.) WiL Fund II L.P.	passive	111.0K	¥1,360	+48.8%	¥115M ($740K)
2024-04-08	SELL	Market Buy	三井住友DSアセットマネジメント株式会社 Sumitomo Mitsui DS Asset Management Company, Limited	other	0	¥2,040	+65.9%	¥19M ($124K)
2024-04-08	BUY	Market Buy	STRIVE株式会社、天野雄介、堤達生 STRIVE Co., Ltd., Yusuke Amano, Tatsuo Tsutsumi	unknown	60.2K	¥2,040	-65.9%	¥123M ($792K)
2024-04-08	BUY	Market Buy	堤達生 Tatsuo Tsutsumi	passive	60.2K	¥2,040	-65.9%	¥1M ($8K)
2024-04-08	BUY	Market Buy	天野雄介 Yusuke Amano	passive	60.2K	¥2,040	-65.9%	¥1M ($8K)
2024-04-08	BUY	unknown	ウィルファンドツーエルピー(WiL Fund II L.P.) WiL Fund II L.P.	unknown	111.0K	¥2,040	-65.9%	¥161M ($1.0M)
2024-04-08	BUY	unknown	株式会社マネーフォワード Money Forward, Inc.	strategic	398.0K	¥2,040	-65.9%	¥812M ($5.2M)
2024-04-08	BUY	Market Buy	STRIVE株式会社 STRIVE, Inc.	passive	60.2K	¥2,040	-65.9%	¥1M ($8K)
2024-04-08	SELL	Market Buy	本間真彦 Masahiko Homma	passive	194.8K	¥2,040	+65.9%	¥382M ($2.5M)
2024-04-08	SELL	Market Buy	SMBCベンチャーキャピタル株式会社 SMBC Venture Capital Co., Ltd	passive	34.9K	¥2,040	+65.9%	¥54M ($351K)
2024-04-08	BUY	unknown	株式会社マネーフォワード Money Forward, Inc.	strategic	398.0K	¥2,040	-65.9%	¥812M ($5.2M)
2024-04-08	BUY	Market Buy	ウィルファンドツーエルピー(WiL Fund II L.P.) WiL Fund II L.P.	passive	111.0K	¥2,040	-65.9%	¥172M ($1.1M)
2024-04-05	BUY	unknown	エー・アイ・キャピタル株式会社 Alternative Investment Capital Limited	other	0	¥1,640	-57.6%	-
2024-04-05	SELL	unknown	三井住友DSアセットマネジメント株式会社 Sumitomo Mitsui DS Asset Management Company, Limited	unknown	0	¥1,640	+57.6%	¥15M ($100K)
2024-04-05	SELL	unknown	SMBCベンチャーキャピタル株式会社 SMBC Venture Capital Co., Ltd	unknown	34.9K	¥1,640	+57.6%	¥44M ($282K)
2024-04-05	SELL	Market Buy	大和企業投資株式会社 Daiwa Corporate Investment Co., Ltd.	passive	92.3K	¥1,640	+57.6%	¥115M ($743K)
2023-12-25	BUY	Market Buy	STRIVE株式会社、天野雄介、堤達生 STRIVE Co., Ltd., Yusuke Amano, Tatsuo Tsutsumi	unknown	103.1K	¥1,472	-52.7%	¥152M ($979K)
2023-12-25	BUY	Market Buy	堤達生 Tatsuo Tsutsumi	passive	103.1K	¥1,472	-52.7%	¥152M ($979K)
2023-12-25	BUY	Market Buy	天野雄介 Yusuke Amano	passive	103.1K	¥1,472	-52.7%	¥152M ($979K)
2023-12-25	BUY	Market Buy	STRIVE株式会社、天野雄介、堤達生 STRIVE Co., Ltd., Yusuke Amano, Tatsuo Tsutsumi	unknown	103.1K	¥1,472	-52.7%	¥152M ($979K)
2023-12-25	BUY	Market Buy	堤達生 Tatsuo Tsutsumi	passive	103.1K	¥1,472	-52.7%	¥152M ($979K)
2023-12-25	BUY	Market Buy	天野雄介 Yusuke Amano	passive	103.1K	¥1,472	-52.7%	¥152M ($979K)
2023-12-25	BUY	Market Buy	STRIVE株式会社 STRIVE, Inc.	passive	103.1K	¥1,472	-52.7%	¥152M ($979K)
2023-12-25	BUY	Market Buy	STRIVE株式会社 STRIVE, Inc.	passive	103.1K	¥1,472	-52.7%	¥152M ($979K)
2023-10-12	BUY	Market Buy	三井住友DSアセットマネジメント株式会社 Sumitomo Mitsui DS Asset Management Company, Limited	passive	9.1K	¥1,701	-59.1%	¥15M ($100K)
2023-10-12	BUY	Market Buy	STRIVE株式会社、天野雄介、堤達生 STRIVE Co., Ltd., Yusuke Amano, Tatsuo Tsutsumi	unknown	103.1K	¥1,701	-59.1%	¥175M ($1.1M)
2023-10-12	BUY	Market Buy	堤達生 Tatsuo Tsutsumi	passive	103.1K	¥1,701	-59.1%	¥175M ($1.1M)
2023-10-12	BUY	Market Buy	天野雄介 Yusuke Amano	passive	103.1K	¥1,701	-59.1%	¥175M ($1.1M)
2023-10-12	BUY	Market Buy	STRIVE株式会社 STRIVE, Inc.	passive	103.1K	¥1,701	-59.1%	¥175M ($1.1M)
2023-10-12	BUY	Market Buy	SMBCベンチャーキャピタル株式会社 SMBC Venture Capital Co., Ltd	passive	59.8K	¥1,701	-59.1%	¥102M ($657K)
2023-10-11	BUY	unknown	三井住友DSアセットマネジメント株式会社 Sumitomo Mitsui DS Asset Management Company, Limited	unknown	9.1K	¥1,750	-60.2%	¥16M ($103K)
2023-10-11	BUY	unknown	SMBCベンチャーキャピタル株式会社 SMBC Venture Capital Co., Ltd	unknown	59.8K	¥1,750	-60.2%	¥105M ($676K)
2023-10-11	BUY	unknown	株式会社ブルーマンデイ Blue Monday	activist	340.0K	¥1,750	-60.2%	¥595M ($3.8M)
2023-10-11	BUY	unknown	エー・アイ・キャピタル株式会社 Alternative Investment Capital Limited	other	0	¥1,750	-60.2%	-
2023-10-11	BUY	Market Buy	大和企業投資株式会社 Daiwa Corporate Investment Co., Ltd.	passive	158.1K	¥1,750	-60.2%	¥277M ($1.8M)
2023-10-11	BUY	Market Buy	本間真彦 Masahiko Homma	passive	371.6K	¥1,750	-60.2%	¥650M ($4.2M)
2023-10-10	BUY	Market Buy	ウィルファンドツーエルピー(WiL Fund II L.P.) WiL Fund II L.P.	passive	190.0K	¥1,916	-63.7%	¥364M ($2.3M)
2023-10-10	BUY	Market Buy	ウィルファンドツーエルピー(WiL Fund II L.P.) WiL Fund II L.P.	passive	190.0K	¥1,916	-63.7%	¥364M ($2.3M)

Frequently asked questions

Who has been buying Caster Co.Ltd. stock?: 13 distinct investors have filed 20 disclosed large-shareholding filings in Caster Co.Ltd. (9331), most recently on 2025-12-12. Each filer, their role, the number of shares and the price at filing are listed in the table on this page.
How many insider filings does Caster Co.Ltd. have?: Caster Co.Ltd. has 20 buy-side and 7 sell-side disclosures on record, covering ¥2.8B ($18.1M) in total reported value, spanning 2023-10-10 to 2025-12-12.
Where does StockDrifts get Caster Co.Ltd. insider data?: From EDINET large-shareholding (5%+) reports — the official filing system run by the Financial Services Agency (Japan). StockDrifts parses each disclosure and matches it to daily price history; the original filings remain available directly from EDINET.
Do insider buys in Japanese stocks predict returns?: Not uniformly. StockDrifts scored 101,000+ Japanese large-shareholding filings on fixed 12-month forward returns and found the predictive power concentrated in specific filer types and filing patterns rather than spread evenly across all disclosures.

Source filings

Every trade listed above is disclosed in EDINET large-shareholding (5%+) reports, filed with the Financial Services Agency (Japan). View the original EDINET filings for Caster Co.Ltd.. For how StockDrifts scores these disclosures, see the Japan insider signal tier research, or browse every Japanese stock we track.