Who has been buying TriIs Incorporated stock?

7 distinct investors have filed 26 disclosed large-shareholding filings in TriIs Incorporated (4840), most recently on 2026-05-12. 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 TriIs Incorporated have?

TriIs Incorporated has 26 buy-side and 3 sell-side disclosures on record, covering ¥1.2B ($7.9M) in total reported value, spanning 2021-12-28 to 2026-05-12.

Where does StockDrifts get TriIs Incorporated 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.

TriIs Incorporated 4840

Company

株式会社トライアイズTriIs Incorporated

Investors

Buys

Total Value

¥1.2B ($7.9M)

Avg Return

+118.89%

Last Filing

2026-05-12

TriIs Incorporated (4840) has 26 disclosed large-shareholding filings and 3 disclosed disposals on record, filed by 7 distinct investors. Together those filings cover ¥1.2B ($7.9M) in reported transaction value. The earliest filing StockDrifts holds for TriIs Incorporated is dated 2021-12-28; the most recent is 2026-05-12. 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 +118.89%, 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
2026-07-24	SELL	Market Buy	池田有希子 Yukiko Ikeda	passive	948.9K	¥558	+0.5%	¥48M ($311K)
2026-07-24	BUY	Market Buy	池田有希子 Yukiko Ikeda	passive	948.9K	¥558	-0.5%	¥48M ($311K)
2026-06-30	SELL	subscription	有限会社キャピタル・マネジメント Capital Management	activist	2.2M	¥615	+9.4%	¥18M ($113K)
2026-05-29	BUY	subscription	岩尾俊兵 SHUMPEI IWAO	other	750.7K	¥978	-35.6%	¥190M ($1.2M)
2026-05-29	BUY	subscription	岩尾俊兵 SHUMPEI IWAO	other	750.7K	¥978	-35.6%	¥190M ($1.2M)
2026-05-12	BUY	Market Buy	南壮栄 Chanyon Minami	activist	862.7K	¥842	-4.5%	¥51M ($329K)
2026-05-01	BUY	Market Buy	南壮栄 Chanyon Minami	activist	495.7K	¥765	+8.2%	¥379M ($2.4M)
2026-05-01	BUY	Market Buy	南壮栄 Chanyon Minami	activist	611.7K	¥765	+8.2%	¥89M ($574K)
2026-05-01	BUY	Market Buy	南壮栄 Chanyon Minami	activist	719.0K	¥765	+8.2%	¥82M ($528K)
2026-05-01	BUY	Market Buy	南壮栄 Chanyon Minami	activist	802.0K	¥765	+8.2%	¥63M ($410K)
2026-05-01	BUY	Market Buy	南壮栄 Chanyon Minami	activist	611.8K	¥765	+8.2%	¥89M ($574K)
2026-05-01	BUY	Market Buy	南壮栄 Chanyon Minami	activist	495.7K	¥765	+8.2%	¥379M ($2.4M)
2026-05-01	BUY	Market Buy	南壮栄 Chanyon Minami	activist	802.0K	¥765	+8.2%	¥63M ($410K)
2026-05-01	BUY	Market Buy	南壮栄 Chanyon Minami	activist	719.0K	¥765	+8.2%	¥82M ($528K)
2026-04-22	SELL	Market Buy	池田有希子 YUKIKO IKEDA	passive	1.0M	¥1,009	+19.6%	¥105M ($675K)
2026-04-09	SELL	Market Buy	FOU JOHN CHI CHONG John Fou	activist	400.0K	¥880	+0.9%	¥92M ($594K)
2026-04-01	SELL	subscription	有限会社キャピタル・マネジメント Capital Management	activist	2.3M	¥788	-5.2%	¥322M ($2.1M)
2026-04-01	BUY	subscription	有限会社キャピタル・マネジメント Capital Management	activist	2.3M	¥788	+5.2%	¥1.8B ($11.6M)
2026-03-26	BUY	unknown	岩尾俊兵 Shumpei Iwao	activist	498.0K	¥517	+101.5%	¥257M ($1.7M)
2026-03-24	BUY	subscription	有限会社キャピタル・マネジメント Capital Management	activist	2.8M	¥429	+142.9%	¥591M ($3.8M)
2026-01-20	BUY	Market Buy	FOU JOHN CHI CHONG John Fou	activist	505.0K	¥502	+107.6%	¥42M ($274K)
2026-01-20	BUY	Market Buy	FOU JOHN CHI CHONG John Fou	activist	505.0K	¥502	+107.6%	¥42M ($274K)
2025-11-27	BUY	Market Buy	有限会社キャピタル・マネジメント Capital Management	activist	898.7K	¥485	+114.8%	¥41M ($265K)
2025-11-10	BUY	Market Buy	FOU JOHN CHI CHONG John Fou	passive	420.0K	¥497	+109.7%	¥209M ($1.3M)
2025-10-08	BUY	Market Buy	有限会社キャピタル・マネジメント Capital Management	activist	814.4K	¥485	+114.8%	¥80M ($517K)
2025-10-08	BUY	Market Buy	有限会社キャピタル・マネジメント Capital Management	activist	814.4K	¥485	+114.8%	¥80M ($517K)
2025-10-02	BUY	Market Buy	有限会社キャピタル・マネジメント Capital Management	activist	648.7K	¥489	+113.1%	¥317M ($2.0M)
2023-02-21	BUY	Market Buy	UGSアセットマネジメント株式会社 UGS Asset Management Co.,Ltd.	activist	837.2K	¥397	+162.5%	¥35M ($223K)
2023-02-21	BUY	subscription	池田均(相続人代表池田有希子) Hitoshi Ikeda(Yukiko Ikeda)	activist	601.6K	¥397	+162.5%	¥38M ($246K)
2023-02-21	BUY	subscription	池田有希子 Yukiko Ikeda	activist	472.6K	¥397	+162.5%	¥16M ($104K)
2023-02-21	BUY	subscription	池田均(相続人代表池田有希子) Hitoshi Ikeda(Yukiko Ikeda)	activist	568.8K	¥397	+162.5%	¥226M ($1.5M)
2023-02-21	BUY	subscription	池田均(相続人代表池田有希子) Hitoshi Ikeda(Yukiko Ikeda)	activist	682.6K	¥397	+162.5%	¥43M ($278K)
2023-02-21	BUY	subscription	池田均(相続人代表池田有希子) Hitoshi Ikeda(Yukiko Ikeda)	other	721.6K	¥397	+162.5%	¥31M ($198K)
2023-02-21	BUY	unknown	池田有希子 Yukiko Ikeda	activist	429.2K	¥397	+162.5%	¥170M ($1.1M)
2023-02-21	BUY	Market Buy	池田有希子 Yukiko Ikeda	activist	1.1M	¥397	+162.5%	¥275M ($1.8M)
2023-02-21	BUY	subscription	池田均(相続人代表池田有希子) Hitoshi Ikeda(Yukiko Ikeda)	other	721.6K	¥397	+162.5%	¥31M ($198K)
2023-01-04	BUY	Market Buy	UGSアセットマネジメント株式会社 UGS Asset Management Co.,Ltd.	activist	750.0K	¥395	+163.8%	¥39M ($250K)
2022-12-15	BUY	Market Buy	UGSアセットマネジメント株式会社 UGS Asset Management Co.,Ltd.	activist	652.2K	¥486	+114.4%	¥47M ($302K)
2022-12-12	BUY	Market Buy	UGSアセットマネジメント株式会社 UGS Asset Management Co.,Ltd.	activist	555.8K	¥462	+125.5%	¥63M ($408K)
2022-11-14	BUY	Market Buy	UGSアセットマネジメント株式会社 UGS Asset Management Co.,Ltd.	activist	418.8K	¥402	+159.2%	¥168M ($1.1M)
2021-12-28	BUY	unknown	池田有希子 Yukiko Ikeda	activist	1.1M	¥331	+214.8%	¥379M ($2.4M)
2021-12-28	BUY	unknown	池田有希子 Yukiko Ikeda	activist	1.1M	¥331	+214.8%	¥379M ($2.4M)

Frequently asked questions

Who has been buying TriIs Incorporated stock?: 7 distinct investors have filed 26 disclosed large-shareholding filings in TriIs Incorporated (4840), most recently on 2026-05-12. 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 TriIs Incorporated have?: TriIs Incorporated has 26 buy-side and 3 sell-side disclosures on record, covering ¥1.2B ($7.9M) in total reported value, spanning 2021-12-28 to 2026-05-12.
Where does StockDrifts get TriIs Incorporated 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 TriIs Incorporated. For how StockDrifts scores these disclosures, see the Japan insider signal tier research, or browse every Japanese stock we track.