Who has been buying KANMONKAI Co., Ltd. stock?

6 distinct investors have filed 6 disclosed large-shareholding filings in KANMONKAI Co., Ltd. (3372), most recently on 2026-05-13. 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 KANMONKAI Co., Ltd. have?

KANMONKAI Co., Ltd. has 6 buy-side and 7 sell-side disclosures on record, covering ¥306M ($2.0M) in total reported value, spanning 2021-03-17 to 2026-05-13.

Where does StockDrifts get KANMONKAI 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.

KANMONKAI Co., Ltd. 3372

Company

株式会社関門海KANMONKAI Co., Ltd.

Investors

Buys

Total Value

¥306M ($2.0M)

Avg Return

-2.81%

Last Filing

2026-05-13

KANMONKAI Co., Ltd. (3372) has 6 disclosed large-shareholding filings and 7 disclosed disposals on record, filed by 6 distinct investors. Together those filings cover ¥306M ($2.0M) in reported transaction value. The earliest filing StockDrifts holds for KANMONKAI Co., Ltd. is dated 2021-03-17; the most recent is 2026-05-13. 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 -2.81%, 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
2026-05-13	BUY	unknown	田原久美子	activist	250.9K	¥220	+0.0%	¥55M ($356K)
2026-05-13	BUY	Market Buy	株式会社椿台代表取締役社長田原久美子	strategic	4.2M	¥220	+0.0%	¥18M ($117K)
2026-05-13	BUY	unknown	田原久美子	activist	250.9K	¥220	+0.0%	¥55M ($356K)
2026-05-13	BUY	Market Buy	株式会社椿台代表取締役社長田原久美子	strategic	4.2M	¥220	+0.0%	¥18M ($117K)
2024-12-03	BUY	Market Buy	株式会社椿台 TSUBAKIDAI Co.,Ltd.	strategic	4.1M	¥219	+1.8%	¥31M ($200K)
2024-12-03	BUY	negotiated	株式会社椿台 TSUBAKIDAI Co.,Ltd.	strategic	4.1M	¥219	+1.8%	¥31M ($200K)
2024-03-06	SELL	subscription	株式会社椿台 TSUBAKIDAI Co.,Ltd.	strategic	3.3M	¥279	+20.1%	¥102M ($660K)
2024-03-06	BUY	subscription	株式会社椿台 TSUBAKIDAI Co.,Ltd.	strategic	4.0M	¥279	-20.1%	¥176M ($1.1M)
2024-03-06	BUY	subscription	株式会社椿台 TSUBAKIDAI Co.,Ltd.	strategic	3.3M	¥279	-20.1%	¥102M ($660K)
2024-03-06	BUY	negotiated	株式会社椿台 TSUBAKIDAI Co.,Ltd.	strategic	4.0M	¥279	-20.1%	¥176M ($1.1M)
2024-03-04	SELL	unknown	サントリー株式会社 SUNTORY SPIRITS LIMITED	other	698.1K	¥283	+21.2%	¥136M ($874K)
2022-09-20	SELL	subscription	株式会社椿台 TSUBAKIDAI Co.,Ltd.	strategic	3.1M	¥224	+0.5%	¥45M ($291K)
2022-09-20	BUY	subscription	株式会社椿台 TSUBAKIDAI Co.,Ltd.	strategic	3.6M	¥224	-0.5%	¥38M ($247K)
2022-09-20	BUY	Market Buy	株式会社椿台 TSUBAKIDAI Co.,Ltd.	strategic	3.8M	¥224	-0.5%	¥43M ($279K)
2022-09-20	BUY	subscription	株式会社椿台 TSUBAKIDAI Co.,Ltd.	strategic	3.1M	¥224	-0.5%	¥45M ($291K)
2022-09-20	BUY	subscription	株式会社椿台 TSUBAKIDAI Co.,Ltd.	strategic	3.8M	¥224	-0.5%	¥34M ($216K)
2022-09-20	BUY	subscription	株式会社椿台 TSUBAKIDAI Co.,Ltd.	strategic	3.8M	¥224	-0.5%	¥861M ($5.6M)
2022-07-25	SELL	unknown	サントリー酒類株式会社 Suntory Liquors Limited	unknown	0	¥218	-2.3%	¥286M ($1.8M)
2022-07-25	BUY	unknown	サントリー株式会社 SUNTORY SPIRITS LIMITED	other	1.2M	¥218	+2.3%	¥257M ($1.7M)
2021-03-24	SELL	Market Buy	マイルストーン・キャピタル・マネジメント株式会社 Milestone Capital Management,Ltd.	passive	615.4K	¥320	+30.3%	¥39M ($253K)
2021-03-17	SELL	Market Buy	マイルストーン・キャピタル・マネジメント株式会社 Milestone Capital Management,Ltd.	passive	739.8K	¥318	+29.9%	¥50M ($323K)
2021-03-17	SELL	Market Buy	M&Aグローバル・パートナーズ株式会社 M&A Global Partners Co.,Ltd.	passive	629.7K	¥318	+29.9%	¥51M ($332K)

Frequently asked questions

Who has been buying KANMONKAI Co., Ltd. stock?: 6 distinct investors have filed 6 disclosed large-shareholding filings in KANMONKAI Co., Ltd. (3372), most recently on 2026-05-13. 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 KANMONKAI Co., Ltd. have?: KANMONKAI Co., Ltd. has 6 buy-side and 7 sell-side disclosures on record, covering ¥306M ($2.0M) in total reported value, spanning 2021-03-17 to 2026-05-13.
Where does StockDrifts get KANMONKAI 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 KANMONKAI Co., Ltd.. For how StockDrifts scores these disclosures, see the Japan insider signal tier research, or browse every Japanese stock we track.