Who has been buying Okumura Corporation stock?

7 distinct investors have filed 5 disclosed large-shareholding filings in Okumura Corporation (1833), most recently on 2025-09-19. 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 Okumura Corporation have?

Okumura Corporation has 5 buy-side and 12 sell-side disclosures on record, covering ¥3.2B ($20.4M) in total reported value, spanning 2021-10-14 to 2025-09-19.

Where does StockDrifts get Okumura Corporation 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.

Okumura Corporation 1833

Company

株式会社奥村組Okumura Corporation

Investors

Buys

Total Value

¥3.2B ($20.4M)

Avg Return

+77.15%

Last Filing

2025-09-19

Okumura Corporation (1833) has 5 disclosed large-shareholding filings and 12 disclosed disposals on record, filed by 7 distinct investors. Together those filings cover ¥3.2B ($20.4M) in reported transaction value. The earliest filing StockDrifts holds for Okumura Corporation is dated 2021-10-14; the most recent is 2025-09-19. 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 +77.15%, 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
2025-09-19	BUY	negotiated	アモーヴァ・アセットマネジメント株式会社 Amova Asset Management Co., Ltd.	other	503.4K	¥4,810	+27.2%	¥56M ($360K)
2025-09-19	SELL	negotiated	三井住友トラスト・アセットマネジメント株式会社 Sumitomo Mitsui Trust Asset Management Co.,Ltd.	other	887.4K	¥4,810	-27.2%	¥930M ($6.0M)
2025-09-19	SELL	negotiated	三井住友信託銀行株式会社 Sumitomo Mitsui Trust Bank,Limited	strategic	400.0K	¥4,810	-27.2%	¥428M ($2.8M)
2023-06-06	BUY	Market Buy	株式会社関西みらい銀行 Kansai Mirai Bank, Ltd.	strategic	71.6K	¥3,960	+54.5%	¥284M ($1.8M)
2023-06-06	SELL	Market Buy	りそなアセットマネジメント株式会社 Resona Asset Management Co., Ltd.	other	585.3K	¥3,960	-54.5%	¥322M ($2.1M)
2023-06-06	BUY	Market Buy	株式会社りそな銀行 Resona Bank, Limited.	strategic	1.5M	¥3,960	+54.5%	¥1.1B ($7.0M)
2023-02-01	SELL	subscription	シルチェスター・インターナショナル・インベスターズ・エルエルピー (Silchester International Investors LLP) Silchester International Investors LLP	activist	1.8M	¥2,997	-104.2%	¥1.2B ($7.6M)
2023-01-13	SELL	subscription	シルチェスター・インターナショナル・インベスターズ・エルエルピー (Silchester International Investors LLP) Silchester International Investors LLP	activist	2.2M	¥2,946	-107.7%	¥1.2B ($7.4M)
2022-12-01	SELL	subscription	シルチェスター・インターナショナル・インベスターズ・エルエルピー (Silchester International Investors LLP) Silchester International Investors LLP	activist	2.6M	¥2,901	-111.0%	¥1.1B ($7.3M)
2022-09-14	SELL	subscription	シルチェスター・インターナショナル・インベスターズ・エルエルピー (Silchester International Investors LLP) Silchester International Investors LLP	activist	3.0M	¥2,970	-106.1%	¥1.2B ($7.7M)
2022-04-21	BUY	negotiated	りそなアセットマネジメント株式会社 Resona Asset Management Co., Ltd.	other	665.4K	¥3,040	+101.3%	¥2.0B ($13.1M)
2022-04-21	BUY	negotiated	株式会社関西みらい銀行 Kansai Mirai Bank, Ltd.	strategic	71.6K	¥3,040	+101.3%	¥218M ($1.4M)
2022-04-21	BUY	negotiated	株式会社りそな銀行 Resona Bank, Limited.	strategic	1.2M	¥3,040	+101.3%	¥3.7B ($23.8M)
2022-03-25	SELL	subscription	シルチェスター・インターナショナル・インベスターズ・エルエルピー (Silchester International Investors LLP) Silchester International Investors LLP	activist	3.5M	¥3,150	-94.3%	¥1.3B ($8.4M)
2022-02-15	SELL	subscription	シルチェスター・インターナショナル・インベスターズ・エルエルピー (Silchester International Investors LLP) Silchester International Investors LLP	activist	3.9M	¥3,255	-88.0%	¥1.4B ($8.8M)
2022-01-12	SELL	subscription	シルチェスター・インターナショナル・インベスターズ・エルエルピー (Silchester International Investors LLP) Silchester International Investors LLP	activist	4.3M	¥3,300	-85.5%	¥1.4B ($8.9M)
2021-12-06	SELL	subscription	シルチェスター・インターナショナル・インベスターズ・エルエルピー (Silchester International Investors LLP) Silchester International Investors LLP	activist	4.7M	¥3,250	-88.3%	¥1.3B ($8.5M)
2021-10-14	SELL	subscription	シルチェスター・インターナショナル・インベスターズ・エルエルピー (Silchester International Investors LLP) Silchester International Investors LLP	activist	5.1M	¥2,977	-105.6%	¥1.2B ($7.8M)

Frequently asked questions

Who has been buying Okumura Corporation stock?: 7 distinct investors have filed 5 disclosed large-shareholding filings in Okumura Corporation (1833), most recently on 2025-09-19. 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 Okumura Corporation have?: Okumura Corporation has 5 buy-side and 12 sell-side disclosures on record, covering ¥3.2B ($20.4M) in total reported value, spanning 2021-10-14 to 2025-09-19.
Where does StockDrifts get Okumura Corporation 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 Okumura Corporation. For how StockDrifts scores these disclosures, see the Japan insider signal tier research, or browse every Japanese stock we track.