Who has been buying Iwabuchi Corporation stock?

6 distinct investors have filed 13 disclosed large-shareholding filings in Iwabuchi Corporation (5983), 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 Iwabuchi Corporation have?

Iwabuchi Corporation has 13 buy-side and 9 sell-side disclosures on record, covering ¥1.9B ($12.0M) in total reported value, spanning 2021-06-25 to 2026-05-13.

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.

Iwabuchi Corporation 5983

Company

イワブチ株式会社Iwabuchi Corporation

Investors

Buys

Total Value

¥1.9B ($12.0M)

Avg Return

+59.91%

Last Filing

2026-05-13

Iwabuchi Corporation (5983) has 13 disclosed large-shareholding filings and 9 disclosed disposals on record, filed by 6 distinct investors. Together those filings cover ¥1.9B ($12.0M) in reported transaction value. The earliest filing StockDrifts holds for Iwabuchi Corporation is dated 2021-06-25; the most recent is 2026-05-13. Across these filings the average return since disclosure is +59.91%, 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
2026-08-21	BUY	unknown	センジン・キャピタル・ピーティーワイ・リミテッド SENJIN CAPITAL PTY LTD	activist	91.0K	¥12,960	-	-
2026-08-21	BUY	Market Buy	ジェームス・ハルス James Halse	activist	10.1K	¥12,960	-	-
2026-07-14	BUY	Market Buy	ジェームス・ハルス James Halse	activist	10.1K	¥13,410	-	-
2026-07-14	BUY	Market Buy	センジン・キャピタル・ピーティーワイ・リミテッド SENJIN CAPITAL PTY LTD	activist	91.0K	¥13,410	+3.6%	¥81M ($523K)
2026-06-09	BUY	Market Buy	センジン・キャピタル・ピーティーワイ・リミテッド SENJIN CAPITAL PTY LTD	activist	84.9K	¥13,520	+2.8%	¥162M ($1.0M)
2026-06-09	SELL	Market Buy	ジェームス・ハルス James Halse	activist	10.1K	¥13,520	-2.8%	¥19M ($125K)
2026-05-13	BUY	Market Buy	センジン・キャピタル・ピーティーワイ・リミテッド SENJIN CAPITAL PTY LTD	activist	72.9K	¥14,180	-2.0%	¥170M ($1.1M)
2026-05-13	BUY	Market Buy	ジェームス・ハルス James Halse	activist	11.5K	¥14,180	-	-
2026-01-06	BUY	Market Buy	センジン・キャピタル・ピーティーワイ・リミテッド SENJIN CAPITAL PTY LTD	activist	60.9K	¥11,690	+18.9%	¥189M ($1.2M)
2026-01-06	BUY	Market Buy	ジェームス・ハルス James Halse	activist	11.5K	¥11,690	-	¥134M ($867K)
2025-09-12	BUY	Market Buy	ジェームス・ハルス James Halse	activist	11.5K	¥9,160	+51.8%	¥105M ($680K)
2025-09-12	BUY	Market Buy	センジン・キャピタル・ピーティーワイ・リミテッド SENJIN CAPITAL PTY LTD	activist	44.8K	¥9,160	+51.8%	¥410M ($2.6M)
2025-09-12	BUY	Market Buy	センジン・キャピタル・ピーティーワイ・リミテッド SENJIN CAPITAL PTY LTD	activist	44.8K	¥9,160	+51.8%	¥410M ($2.6M)
2025-09-12	BUY	Market Buy	ジェームス・ハルス James Halse	activist	11.5K	¥9,160	+51.8%	¥105M ($680K)
2025-07-09	SELL	Market Buy	株式会社DOE5パーセント DOE5% Co., Ltd.	activist	21.8K	¥6,540	-112.5%	¥160M ($1.0M)
2025-07-09	SELL	Market Buy	植島幹九郎 Kankuro Ueshima	activist	0	¥6,540	-112.5%	¥22M ($144K)
2025-07-09	SELL	Market Buy	株式会社UESHIMA UESHIMA Co., Ltd.	activist	4.7K	¥6,540	-112.5%	¥9M ($56K)
2025-03-21	BUY	Market Buy	植島幹九郎 Kankuro Ueshima	activist	3.4K	¥6,450	-	-
2025-03-21	BUY	Market Buy	植島幹九郎 Kankuro Ueshima	activist	3.4K	¥6,450	-	-
2025-03-21	BUY	Market Buy	株式会社UESHIMA UESHIMA Co., Ltd.	activist	6.0K	¥6,450	-	-
2025-03-21	SELL	Market Buy	株式会社DOE5パーセント DOE5% Co., Ltd.	activist	43.3K	¥6,450	-115.5%	¥19M ($124K)
2025-03-21	BUY	Market Buy	株式会社UESHIMA UESHIMA Co., Ltd.	activist	6.0K	¥6,450	-	-
2025-03-21	SELL	Market Buy	株式会社DOE5パーセント DOE5% Co., Ltd.	activist	43.3K	¥6,450	-115.5%	¥19M ($124K)
2025-02-18	SELL	Market Buy	植島幹九郎 Kankuro Ueshima	activist	3.4K	¥6,570	-111.6%	¥1.4B ($9.3M)
2025-02-18	SELL	Market Buy	植島幹九郎 Kankuro Ueshima	activist	3.4K	¥6,570	-111.6%	¥1.4B ($9.3M)
2025-02-18	BUY	Market Buy	株式会社UESHIMA UESHIMA Co., Ltd.	activist	6.0K	¥6,570	+111.6%	¥7M ($47K)
2025-02-18	SELL	Market Buy	株式会社DOE5パーセント DOE5% Co., Ltd.	activist	46.3K	¥6,570	-111.6%	¥12M ($75K)
2025-02-18	BUY	Market Buy	株式会社UESHIMA UESHIMA Co., Ltd.	activist	6.0K	¥6,570	+111.6%	¥7M ($47K)
2025-02-18	SELL	Market Buy	株式会社DOE5パーセント DOE5% Co., Ltd.	activist	46.3K	¥6,570	-111.6%	¥12M ($75K)
2024-02-21	BUY	Market Buy	植島幹九郎 Kankuro Ueshima	activist	5.6K	¥7,540	+84.3%	¥42M ($273K)
2024-02-21	BUY	Market Buy	株式会社UESHIMA UESHIMA Co., Ltd.	activist	5.0K	¥7,540	+84.3%	¥37M ($241K)
2024-02-21	BUY	Market Buy	株式会社D&Iインベストメント D&I Investment Co., Ltd.	activist	48.1K	¥7,540	+84.3%	¥362M ($2.3M)
2023-02-27	BUY	Market Buy	イワブチ取引先持株会理事長山口弘 Yamaguchi Hiroshi	strategic	104.3K	¥4,790	+190.2%	¥53M ($340K)
2021-06-25	BUY	Market Buy	イワブチ取引先持株会理事長山口弘 HIROSHI YAMAGIUCHI	strategic	93.3K	¥5,870	+136.8%	¥66M ($425K)

Frequently asked questions

Who has been buying Iwabuchi Corporation stock?: 6 distinct investors have filed 13 disclosed large-shareholding filings in Iwabuchi Corporation (5983), 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 Iwabuchi Corporation have?: Iwabuchi Corporation has 13 buy-side and 9 sell-side disclosures on record, covering ¥1.9B ($12.0M) in total reported value, spanning 2021-06-25 to 2026-05-13.
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.