Who has been buying Suido Kiko Kaisha, Ltd. stock?

4 distinct investors have filed 2 disclosed large-shareholding filings in Suido Kiko Kaisha, Ltd. (6403), most recently on 2026-03-31. 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 Suido Kiko Kaisha, Ltd. have?

Suido Kiko Kaisha, Ltd. has 2 buy-side and 3 sell-side disclosures on record, covering ¥9M ($59K) in total reported value, spanning 2021-06-22 to 2026-03-31.

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.

Suido Kiko Kaisha, Ltd. 6403

Company

水道機工株式会社Suido Kiko Kaisha, Ltd.

Investors

Buys

Total Value

¥9M ($59K)

Avg Return

+41.75%

Last Filing

2026-03-31

Suido Kiko Kaisha, Ltd. (6403) has 2 disclosed large-shareholding filings and 3 disclosed disposals on record, filed by 4 distinct investors. Together those filings cover ¥9M ($59K) in reported transaction value. The earliest filing StockDrifts holds for Suido Kiko Kaisha, Ltd. is dated 2021-06-22; the most recent is 2026-03-31. Across these filings the average return since disclosure is +41.75%, 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
2026-03-31	SELL	unknown	光通信株式会社 Hikari Tsushin K.K.	unknown	0	¥4,015	+0.0%	¥880M ($5.7M)
2026-03-30	BUY	unknown	東レ株式会社	activist	2.2M	¥4,015	-	-
2026-03-30	BUY	unknown	メタウォーター株式会社	activist	1.5M	¥4,015	-	¥6.0B ($38.7M)
2026-02-12	BUY	unknown	東レ株式会社 Toray Industries, Inc.	activist	2.2M	¥4,045	-	-
2026-02-12	BUY	unknown	東レ株式会社 Toray Industries, Inc.	strategic	11.0M	¥4,045	-	¥18.9B ($122.0M)
2026-02-12	BUY	unknown	東レ株式会社 Toray Industries, Inc.	strategic	4.3M	¥4,045	-	¥4.3B ($27.9M)
2026-02-12	BUY	unknown	東レ株式会社 Toray Industries, Inc.	strategic	3.3M	¥4,045	-	¥1.2B ($7.8M)
2025-09-29	BUY	Market Buy	光通信株式会社 Hikari Tsushin K.K.	passive	219.1K	¥3,050	+31.6%	¥9M ($59K)
2025-09-02	BUY	Market Buy	光通信株式会社 Hikari Tsushin K.K.	passive	215.9K	¥2,644	+51.9%	¥571M ($3.7M)
2024-06-07	SELL	Market Buy	シンプレクス・アセット・マネジメント株式会社 Simplex Asset Management Co., Ltd.	passive	176.3K	¥1,838	-118.4%	¥90M ($581K)
2021-06-22	SELL	Market Buy	シンプレクス・アセット・マネジメント株式会社 Simplex Asset Management Co., Ltd.	passive	225.2K	¥1,974	-103.4%	¥87M ($564K)

Frequently asked questions

Who has been buying Suido Kiko Kaisha, Ltd. stock?: 4 distinct investors have filed 2 disclosed large-shareholding filings in Suido Kiko Kaisha, Ltd. (6403), most recently on 2026-03-31. 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 Suido Kiko Kaisha, Ltd. have?: Suido Kiko Kaisha, Ltd. has 2 buy-side and 3 sell-side disclosures on record, covering ¥9M ($59K) in total reported value, spanning 2021-06-22 to 2026-03-31.
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.