Who has been buying Nagaoka International Corporation stock?

6 distinct investors have filed 6 disclosed large-shareholding filings in Nagaoka International Corporation (6239), most recently on 2026-02-16. 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 Nagaoka International Corporation have?

Nagaoka International Corporation has 6 buy-side and 2 sell-side disclosures on record, covering ¥3.7B ($23.7M) in total reported value, spanning 2022-02-18 to 2026-02-16.

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.

Nagaoka International Corporation 6239

Company

株式会社ナガオカNagaoka International Corporation

Investors

Buys

Total Value

¥3.7B ($23.7M)

Avg Return

+26.11%

Last Filing

2026-02-16

Nagaoka International Corporation (6239) has 6 disclosed large-shareholding filings and 2 disclosed disposals on record, filed by 6 distinct investors. Together those filings cover ¥3.7B ($23.7M) in reported transaction value. The earliest filing StockDrifts holds for Nagaoka International Corporation is dated 2022-02-18; the most recent is 2026-02-16. Across these filings the average return since disclosure is +26.11%, 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
2026-05-22	BUY	Market Buy	株式会社フラクタル・ビジネス	activist	133.6K	¥1,306	-	-
2026-05-22	BUY	Market Buy	奥村学	activist	451.4K	¥1,306	+9.5%	¥106M ($686K)
2026-05-22	BUY	Market Buy	株式会社フラクタル・ビジネス	activist	133.6K	¥1,306	+9.5%	¥27M ($173K)
2026-05-22	BUY	Market Buy	奥村学	activist	451.4K	¥1,306	+9.5%	¥106M ($686K)
2026-05-15	BUY	Market Buy	奥村学	activist	370.5K	¥1,303	+9.8%	¥69M ($446K)
2026-05-15	BUY	Market Buy	株式会社フラクタル・ビジネス	activist	133.6K	¥1,303	+9.8%	¥27M ($173K)
2026-02-16	BUY	unknown	株式会社フラクタル・ビジネス	other	113.6K	¥1,465	-	-
2026-02-16	BUY	unknown	奥村学	other	317.0K	¥1,465	-2.4%	¥105M ($676K)
2026-01-09	BUY	Market Buy	光通信株式会社	passive	348.0K	¥1,488	-3.9%	¥518M ($3.3M)
2026-01-09	BUY	Market Buy	株式会社UH5	passive	7.1K	¥1,488	-3.9%	¥11M ($68K)
2025-10-06	BUY	unknown	奥村学 Manabu Okumura	other	245.5K	¥1,479	-3.3%	¥363M ($2.3M)
2025-10-06	BUY	unknown	株式会社フラクタル・ビジネス Fractal Business Inc.	other	113.6K	¥1,479	-3.3%	¥168M ($1.1M)
2024-03-21	BUY	unknown	株式会社ハマダグループ HAMADA GROUP CO.,Ltd.	strategic	3.7M	¥1,386	-	¥693M ($4.5M)
2024-03-21	SELL	unknown	株式会社ハマダグループ HAMADA GROUP CO.,Ltd.	strategic	3.7M	¥1,386	-3.2%	¥693M ($4.5M)
2022-02-18	SELL	unknown	株式会社ハマダ HAMADA CO.,LTD	strategic	0	¥671	-113.1%	¥2.8B ($18.1M)
2022-02-18	BUY	unknown	株式会社ハマダグループ HAMADAGROUP CO.,LTD	strategic	4.2M	¥671	+113.1%	¥2.8B ($18.1M)

Frequently asked questions

Who has been buying Nagaoka International Corporation stock?: 6 distinct investors have filed 6 disclosed large-shareholding filings in Nagaoka International Corporation (6239), most recently on 2026-02-16. 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 Nagaoka International Corporation have?: Nagaoka International Corporation has 6 buy-side and 2 sell-side disclosures on record, covering ¥3.7B ($23.7M) in total reported value, spanning 2022-02-18 to 2026-02-16.
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.