Who has been buying Watt Mann Co., Ltd. stock?

12 distinct investors have filed 31 disclosed large-shareholding filings in Watt Mann Co., Ltd. (9927), most recently on 2026-04-21. 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 Watt Mann Co., Ltd. have?

Watt Mann Co., Ltd. has 31 buy-side and 13 sell-side disclosures on record, covering ¥7.4B ($47.6M) in total reported value, spanning 2021-04-06 to 2026-04-21.

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.

Watt Mann Co., Ltd. 9927

Company

株式会社ワットマンWatt Mann Co., Ltd.

Investors

Buys

Total Value

¥7.4B ($47.6M)

Avg Return

+106.80%

Last Filing

2026-04-21

Watt Mann Co., Ltd. (9927) has 31 disclosed large-shareholding filings and 13 disclosed disposals on record, filed by 12 distinct investors. Together those filings cover ¥7.4B ($47.6M) in reported transaction value. The earliest filing StockDrifts holds for Watt Mann Co., Ltd. is dated 2021-04-06; the most recent is 2026-04-21. Across these filings the average return since disclosure is +106.80%, 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
2026-04-21	SELL	unknown	東海東京証券株式会社 Tokai Tokyo Securities Co., Ltd.	other	0	¥963	+0.0%	¥624M ($4.0M)
2026-04-10	SELL	unknown	川畑遥	unknown	0	¥963	+0.0%	¥308M ($2.0M)
2026-04-10	BUY	unknown	IAPF3株式会社	activist	6.3M	¥963	-	-
2026-04-10	BUY	Market Buy	川畑泰史	activist	2.1M	¥963	+0.0%	¥308M ($2.0M)
2026-04-10	SELL	Market Buy	川畑遥	activist	0	¥963	+0.0%	¥308M ($2.0M)
2026-04-09	BUY	unknown	川畑遥	activist	320.2K	¥963	-	-
2026-04-09	BUY	unknown	川畑泰史	activist	1.8M	¥963	-	-
2026-04-09	BUY	unknown	IAPF3株式会社	activist	6.3M	¥963	+0.0%	¥6.0B ($38.9M)
2026-04-09	BUY	unknown	川畑遥	activist	320.2K	¥963	-	-
2026-04-09	BUY	unknown	川畑泰史	activist	1.8M	¥963	-	-
2026-04-09	BUY	unknown	川畑遥	unknown	320.2K	¥963	+0.0%	-
2026-04-06	SELL	Market Buy	株式会社ハードオフコーポレーション HARD OFF CORPORATION Co.,Ltd.	passive	0	¥964	+0.1%	¥1.2B ($8.0M)
2026-03-05	BUY	unknown	東海東京証券株式会社 Tokai Tokyo Securities Co., Ltd.	other	648.7K	¥968	-0.5%	¥628M ($4.1M)
2026-02-20	SELL	unknown	株式会社フラクタル・ビジネス	other	0	¥969	+0.6%	¥293M ($1.9M)
2026-02-20	SELL	unknown	奥村学	other	0	¥969	+0.6%	¥460M ($3.0M)
2026-02-20	SELL	unknown	川畑泰史	activist	1.8M	¥969	+0.6%	¥7M ($45K)
2026-02-20	BUY	unknown	川畑遥	activist	320.2K	¥969	-	-
2026-02-20	SELL	unknown	川畑泰史	activist	1.8M	¥969	+0.6%	¥7M ($45K)
2026-02-20	BUY	unknown	川畑遥	activist	320.2K	¥969	-	-
2026-02-17	BUY	Market Buy	株式会社ハードオフコーポレーション HARD OFF CORPORATION Co.,Ltd.	passive	1.3M	¥968	-0.5%	¥85M ($545K)
2025-10-22	BUY	Market Buy	株式会社フラクタル・ビジネス Fractal Business Inc.	other	301.8K	¥743	-	-
2025-10-22	BUY	Market Buy	奥村学 Manabu Okumura	other	474.4K	¥743	+29.6%	¥9M ($61K)
2025-09-01	BUY	Market Buy	株式会社フラクタル・ビジネス Fractal Business Inc.	other	301.8K	¥759	+26.9%	¥1M ($9K)
2025-09-01	BUY	unknown	株式会社フラクタル・ビジネス Fractal Business Inc.	other	301.8K	¥759	+26.9%	¥1M ($9K)
2025-09-01	BUY	unknown	奥村学 Manabu Okumura	other	461.9K	¥759	+26.9%	¥29M ($187K)
2025-09-01	BUY	Market Buy	奥村学 Manabu Okumura	other	461.9K	¥759	+26.9%	¥29M ($187K)
2025-06-02	BUY	Market Buy	株式会社フラクタル・ビジネス Fractal Business Inc.	other	299.9K	¥762	+26.4%	¥62M ($398K)
2025-06-02	BUY	Market Buy	奥村学 Manabu Okumura	other	424.1K	¥762	+26.4%	¥9M ($58K)
2024-07-12	BUY	Market Buy	株式会社フラクタル・ビジネス Fractal Business Inc.	other	219.0K	¥884	+8.9%	¥44M ($285K)
2024-07-12	BUY	Market Buy	奥村学 Manabu Okumura	other	412.0K	¥884	-	-
2023-01-04	BUY	unknown	株式会社フラクタル・ビジネス Fractal Business Inc.	other	42.4K	¥635.5	+51.5%	¥25M ($163K)
2023-01-04	BUY	Market Buy	株式会社フラクタル・ビジネス Fractal Business Inc.	other	42.4K	¥635.5	+51.5%	¥25M ($163K)
2023-01-04	SELL	Market Buy	奥村学 Manabu Okumura	other	103.0K	¥635.5	-51.5%	¥25M ($164K)
2023-01-04	SELL	unknown	奥村学 Manabu Okumura	other	103.0K	¥635.5	-51.5%	¥25M ($164K)
2022-08-02	BUY	unknown	株式会社フラクタル・ビジネス Fractal Business Inc.	other	2.4K	¥458.75	-	-
2022-08-02	BUY	unknown	奥村学 Manabu Okumura	other	143.0K	¥458.75	+109.9%	¥4M ($25K)
2022-08-02	BUY	unknown	株式会社フラクタル・ビジネス Fractal Business Inc.	other	2.4K	¥458.75	-	-
2022-08-02	BUY	unknown	奥村学 Manabu Okumura	other	143.0K	¥458.75	+109.9%	¥4M ($25K)
2022-05-11	BUY	unknown	奥村学 Manabu Okumura	other	134.6K	¥346.25	-	¥47M ($301K)
2022-05-11	BUY	unknown	株式会社フラクタル・ビジネス Fractal Business Inc.	other	2.4K	¥346.25	-	-
2022-05-11	BUY	unknown	株式会社フラクタル・ビジネス Fractal Business Inc.	other	2.4K	¥346.25	-	¥831K ($5K)
2022-05-11	BUY	unknown	奥村学 Manabu Okumura	other	134.6K	¥346.25	+178.1%	¥8M ($51K)
2021-11-19	BUY	unknown	株式会社フラクタル・ビジネス Fractal Business Inc.	other	1.2K	¥325.38	+196.0%	¥390K ($3K)
2021-11-19	BUY	unknown	株式会社フラクタル・ビジネス Fractal Business Inc.	other	1.2K	¥325.38	+196.0%	¥370K ($2K)
2021-11-19	BUY	unknown	奥村学 Manabu Okumura	other	55.9K	¥325.38	+196.0%	¥18M ($117K)
2021-11-19	BUY	unknown	奥村学 Manabu Okumura	other	55.9K	¥325.38	+196.0%	¥18M ($117K)
2021-08-19	SELL	unknown	株式会社SBI証券 SBI SECURITIES Co.,Ltd.	other	35.2K	¥296.13	-225.2%	¥6M ($41K)
2021-08-05	BUY	Market Buy	川畑遥 Haruka Kawabata	activist	40.0K	¥307.5	-	-
2021-08-05	BUY	Market Buy	川畑泰史 Yasushi Kawabata	activist	224.8K	¥307.5	+213.2%	¥38M ($248K)
2021-08-05	BUY	unknown	川畑遥 Haruka Kawabata	activist	40.0K	¥307.5	-	-

Showing the 50 most recent of 61 filings.

Frequently asked questions

Who has been buying Watt Mann Co., Ltd. stock?: 12 distinct investors have filed 31 disclosed large-shareholding filings in Watt Mann Co., Ltd. (9927), most recently on 2026-04-21. 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 Watt Mann Co., Ltd. have?: Watt Mann Co., Ltd. has 31 buy-side and 13 sell-side disclosures on record, covering ¥7.4B ($47.6M) in total reported value, spanning 2021-04-06 to 2026-04-21.
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.

More on this data

Every trade listed above comes from an official regulatory disclosure. For how StockDrifts scores these disclosures, see the Japan insider signal tier research, or browse every Japanese stock we track.