Who has been buying Japan System Techniques Co., Ltd. stock?

13 distinct investors have filed 51 disclosed large-shareholding filings in Japan System Techniques Co., Ltd. (4323), most recently on 2026-04-22. 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 Japan System Techniques Co., Ltd. have?

Japan System Techniques Co., Ltd. has 51 buy-side and 22 sell-side disclosures on record, covering ¥2.2B ($14.1M) in total reported value, spanning 2021-03-29 to 2026-04-22.

Where does StockDrifts get Japan System Techniques Co., Ltd. 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.

Japan System Techniques Co., Ltd. 4323

Company

日本システム技術株式会社Japan System Techniques Co., Ltd.

Investors

Buys

Total Value

¥2.2B ($14.1M)

Avg Return

+213.39%

Last Filing

2026-04-22

Japan System Techniques Co., Ltd. (4323) has 51 disclosed large-shareholding filings and 22 disclosed disposals on record, filed by 13 distinct investors. Together those filings cover ¥2.2B ($14.1M) in reported transaction value. The earliest filing StockDrifts holds for Japan System Techniques Co., Ltd. is dated 2021-03-29; the most recent is 2026-04-22. 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 +213.39%, 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
2026-04-22	BUY	Market Buy	平林大	strategic	119.0K	¥1,964	-13.3%	¥234M ($1.5M)
2026-04-22	SELL	unknown	平林恵美子	strategic	30.0K	¥1,964	+13.3%	¥7M ($47K)
2026-04-22	SELL	unknown	株式会社ジャスト	strategic	2.9M	¥1,964	+13.3%	¥607M ($3.9M)
2026-04-22	BUY	unknown	平林真実	strategic	160	¥1,964	-13.3%	¥314K ($2K)
2026-04-22	SELL	unknown	平林卓	strategic	278.6K	¥1,964	+13.3%	¥300M ($1.9M)
2026-04-22	SELL	negotiated	平林武昭	activist	192.6K	¥1,964	+13.3%	¥22M ($142K)
2026-04-22	BUY	Market Buy	平林大	strategic	240.7K	¥1,964	-13.3%	¥5M ($31K)
2026-04-22	BUY	unknown	平林恵美子	strategic	60.0K	¥1,964	-13.3%	¥118M ($760K)
2026-04-22	BUY	unknown	株式会社ジャスト	strategic	5.8M	¥1,964	-13.3%	¥11.4B ($73.5M)
2026-04-22	BUY	unknown	平林真実	strategic	320	¥1,964	-13.3%	¥628K ($4K)
2026-04-22	BUY	Market Buy	平林卓	strategic	558.7K	¥1,964	-13.3%	¥5M ($31K)
2026-04-22	BUY	Market Buy	平林武昭	activist	485.9K	¥1,964	-13.3%	¥200M ($1.3M)
2026-04-22	BUY	unknown	平林大	strategic	240.7K	¥1,964	-13.3%	¥473M ($3.0M)
2026-04-22	BUY	unknown	平林恵美子	strategic	60.0K	¥1,964	-13.3%	¥118M ($760K)
2026-04-22	BUY	unknown	株式会社ジャスト	strategic	5.8M	¥1,964	-13.3%	¥11.4B ($73.5M)
2026-04-22	BUY	unknown	平林真実	strategic	320	¥1,964	-13.3%	¥628K ($4K)
2026-04-22	BUY	Market Buy	平林卓	strategic	561.3K	¥1,964	-13.3%	¥5M ($31K)
2026-04-22	BUY	Market Buy	平林武昭	activist	492.1K	¥1,964	-13.3%	¥10M ($63K)
2026-02-12	BUY	Market Buy	ミリ・キャピタル・マネジメント・エルエルシー (MIRI Capital Management LLC) MIRI Capital Management LLC	activist	7.3M	¥2,446	-19.8%	¥626M ($4.0M)
2025-12-18	BUY	Market Buy	ミリ・キャピタル・マネジメント・エルエルシー (MIRI Capital Management LLC) MIRI Capital Management LLC	activist	7.0M	¥2,432	-19.3%	¥610M ($3.9M)
2025-09-25	BUY	Market Buy	ミリ・キャピタル・マネジメント・エルエルシー (MIRI Capital Management LLC) MIRI Capital Management LLC	activist	6.8M	¥2,434	-19.4%	¥617M ($4.0M)
2024-12-02	BUY	Market Buy	ミリ・キャピタル・マネジメント・エルエルシー (MIRI Capital Management LLC) MIRI Capital Management LLC	activist	6.5M	¥1,921	+2.1%	¥487M ($3.1M)
2024-09-26	BUY	Market Buy	ミリ・キャピタル・マネジメント・エルエルシー (MIRI Capital Management LLC) MIRI Capital Management LLC	activist	6.3M	¥1,961	+0.1%	¥511M ($3.3M)
2024-01-12	BUY	Market Buy	ミリ・キャピタル・マネジメント・エルエルシー (MIRI Capital Management LLC) MIRI Capital Management LLC	activist	3.0M	¥1,610	+21.9%	¥202M ($1.3M)
2023-08-30	BUY	Market Buy	ミリ・キャピタル・マネジメント・エルエルシー (MIRI Capital Management LLC) MIRI Capital Management LLC	activist	2.9M	¥1,086	+80.7%	¥136M ($879K)
2023-04-18	BUY	Market Buy	ミリ・キャピタル・マネジメント・エルエルシー (MIRI Capital Management LLC) MIRI Capital Management LLC	activist	2.8M	¥997.5	+96.7%	¥125M ($807K)
2023-01-24	BUY	Market Buy	ミリ・キャピタル・マネジメント・エルエルシー (MIRI Capital Management LLC) MIRI Capital Management LLC	activist	2.6M	¥842	+133.0%	¥108M ($695K)
2022-12-28	BUY	Market Buy	ミリ・キャピタル・マネジメント・エルエルシー (MIRI Capital Management LLC) MIRI Capital Management LLC	activist	2.5M	¥821	+139.0%	¥103M ($664K)
2022-12-05	SELL	unknown	ノムラインターナショナルピーエルシー NOMURA INTERNATIONAL PLC	other	-9.1K	¥811	-141.9%	¥21M ($136K)
2022-12-05	SELL	unknown	野村證券株式会社 Nomura Securities Co.,Ltd.	other	313.7K	¥811	-141.9%	¥75M ($481K)
2022-12-05	BUY	unknown	野村アセットマネジメント株式会社 Nomura Asset Management Co., Ltd.	other	246.6K	¥811	+141.9%	¥12M ($78K)
2022-11-16	BUY	Market Buy	ミリ・キャピタル・マネジメント・エルエルシー (MIRI Capital Management LLC) MIRI Capital Management LLC	activist	2.4M	¥841.5	+133.2%	¥109M ($701K)
2022-10-26	BUY	Market Buy	ミリ・キャピタル・マネジメント・エルエルシー (MIRI Capital Management LLC) MIRI Capital Management LLC	activist	2.2M	¥700	+180.3%	¥88M ($566K)
2022-10-18	BUY	Market Buy	ミリ・キャピタル・マネジメント・エルエルシー (MIRI Capital Management LLC) MIRI Capital Management LLC	activist	2.1M	¥652.5	+200.7%	¥101M ($653K)
2022-10-05	BUY	unknown	野村アセットマネジメント株式会社 Nomura Asset Management Co., Ltd.	other	232.4K	¥601.5	+226.2%	¥140M ($902K)
2022-10-05	SELL	unknown	ノムラインターナショナルピーエルシー NOMURA INTERNATIONAL PLC	other	17.8K	¥601.5	-226.2%	¥4M ($24K)
2022-10-05	SELL	unknown	野村證券株式会社 Nomura Securities Co.,Ltd.	other	406.1K	¥601.5	-226.2%	¥43M ($275K)
2022-09-20	BUY	Market Buy	ミリ・キャピタル・マネジメント・エルエルシー (MIRI Capital Management LLC) MIRI Capital Management LLC	activist	981.4K	¥623.25	+214.8%	¥43M ($277K)
2022-08-15	BUY	Market Buy	ミリ・キャピタル・マネジメント・エルエルシー (MIRI Capital Management LLC) MIRI Capital Management LLC	activist	913.0K	¥611	+221.1%	¥39M ($255K)
2022-07-06	SELL	unknown	野村アセットマネジメント株式会社 Nomura Asset Management Co., Ltd.	other	116.4K	¥601.5	-226.2%	¥2M ($14K)
2022-07-06	SELL	unknown	ノムラインターナショナルピーエルシー NOMURA INTERNATIONAL PLC	other	11.9K	¥601.5	-226.2%	¥25M ($161K)
2022-07-06	SELL	unknown	野村證券株式会社 Nomura Securities Co.,Ltd.	other	238.2K	¥601.5	-226.2%	¥14M ($92K)
2022-07-06	BUY	Market Buy	ミリ・キャピタル・マネジメント・エルエルシー (MIRI Capital Management LLC) MIRI Capital Management LLC	activist	848.3K	¥601.5	+226.2%	¥41M ($263K)
2022-06-08	BUY	Market Buy	ミリ・キャピタル・マネジメント・エルエルシー (MIRI Capital Management LLC) MIRI Capital Management LLC	activist	780.7K	¥620.5	+216.2%	¥39M ($251K)
2022-05-17	BUY	Market Buy	ミリ・キャピタル・マネジメント・エルエルシー (MIRI Capital Management LLC) MIRI Capital Management LLC	activist	717.7K	¥554.75	+253.7%	¥36M ($231K)
2022-04-06	BUY	unknown	野村アセットマネジメント株式会社 Nomura Asset Management Co., Ltd.	other	119.7K	¥665.75	+194.7%	¥827K ($5K)
2022-04-06	SELL	unknown	ノムラインターナショナルピーエルシー NOMURA INTERNATIONAL PLC	other	53.6K	¥665.75	-194.7%	¥148M ($957K)
2022-04-06	BUY	unknown	野村證券株式会社 Nomura Securities Co.,Ltd.	other	262.2K	¥665.75	+194.7%	¥175M ($1.1M)
2022-03-14	BUY	Market Buy	ミリ・キャピタル・マネジメント・エルエルシー (MIRI Capital Management LLC) MIRI Capital Management LLC	activist	653.4K	¥565.5	+246.9%	¥38M ($245K)
2022-02-21	BUY	unknown	野村アセットマネジメント株式会社 Nomura Asset Management Co., Ltd.	other	118.4K	¥520	+277.3%	¥323K ($2K)

Showing the 50 most recent of 95 filings.

Frequently asked questions

Who has been buying Japan System Techniques Co., Ltd. stock?: 13 distinct investors have filed 51 disclosed large-shareholding filings in Japan System Techniques Co., Ltd. (4323), most recently on 2026-04-22. 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 Japan System Techniques Co., Ltd. have?: Japan System Techniques Co., Ltd. has 51 buy-side and 22 sell-side disclosures on record, covering ¥2.2B ($14.1M) in total reported value, spanning 2021-03-29 to 2026-04-22.
Where does StockDrifts get Japan System Techniques Co., Ltd. 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 Japan System Techniques Co., Ltd.. For how StockDrifts scores these disclosures, see the Japan insider signal tier research, or browse every Japanese stock we track.