Who has been buying System Support Inc. stock?

6 distinct investors have filed 15 disclosed large-shareholding filings in System Support Inc. (4396), most recently on 2026-03-23. 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 System Support Inc. have?

System Support Inc. has 15 buy-side and 11 sell-side disclosures on record, covering ¥1.7B ($11.2M) in total reported value, spanning 2021-03-19 to 2026-03-23.

Where does StockDrifts get System Support Inc. 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.

System Support Inc. 4396

Company

株式会社システムサポートホールディングスSystem Support Inc.

Investors

Buys

Total Value

¥1.7B ($11.2M)

Avg Return

+78.21%

Last Filing

2026-03-23

System Support Inc. (4396) has 15 disclosed large-shareholding filings and 11 disclosed disposals on record, filed by 6 distinct investors. Together those filings cover ¥1.7B ($11.2M) in reported transaction value. The earliest filing StockDrifts holds for System Support Inc. is dated 2021-03-19; the most recent is 2026-03-23. 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 +78.21%, 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
2026-07-23	BUY	Market Buy	エフアイエーエムエルエルシー FIAM LLC	other	1.1M	¥1,087	+31.1%	¥124M ($802K)
2026-07-23	BUY	unknown	エフエムアールインベストメントマネジメントユーケーリミテッドLimited) FMR Investment Management (UK	other	66.2K	¥1,087	+31.1%	¥72M ($464K)
2026-07-23	SELL	unknown	フィデリティマネジメントアンドリサーチカンパニーエルエルシー Fidelity Management & Research Company LLC	corporate	202.0K	¥1,087	-31.1%	¥242M ($1.6M)
2026-07-07	BUY	Market Buy	エフアイエーエムエルエルシー FIAM LLC	other	955.7K	¥1,062	+5.0%	¥232M ($1.5M)
2026-07-07	SELL	unknown	フィデリティマネジメントアンドリサーチカンパニーエルエルシー Fidelity Management & Research Company LLC	corporate	424.7K	¥1,062	-5.0%	¥60M ($385K)
2026-06-05	BUY	unknown	エフアイエーエムエルエルシー FIAM LLC	other	636.2K	¥996	+6.3%	¥634M ($4.1M)
2026-06-05	BUY	unknown	エフエムアールインベストメントマネジメントユーケーリミテッドLimited) FMR Investment Management (UK	other	255.8K	¥996	+6.3%	¥255M ($1.6M)
2026-06-05	BUY	unknown	フィデリティマネジメントアンドリサーチカンパニーエルエルシー Fidelity Management & Research Company LLC	corporate	166.0K	¥996	+6.3%	¥165M ($1.1M)
2026-06-05	BUY	Market Buy	エフアイエーエムエルエルシー FIAM LLC	other	736.2K	¥996	+6.3%	¥99M ($642K)
2026-06-05	BUY	Market Buy	フィデリティマネジメントアンドリサーチカンパニーエルエルシー Fidelity Management & Research Company LLC	corporate	480.7K	¥996	+6.3%	¥313M ($2.0M)
2026-03-23	BUY	unknown	エフエムアールエルエルシー(FMR LLC) FMR LLC	other	1.1M	¥1,051	+9.6%	¥1.1B ($7.2M)
2024-06-06	SELL	Market Buy	日興アセットマネジメント株式会社 Nikko Asset Management Co.,Ltd.	other	250.2K	¥895.5	-28.6%	¥100M ($648K)
2024-06-06	BUY	Market Buy	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	181.9K	¥895.5	+28.6%	¥18M ($114K)
2023-01-10	BUY	unknown	野村アセットマネジメント株式会社 Nomura Asset Management Co., Ltd.	other	250.8K	¥693	+66.2%	¥10M ($65K)
2023-01-10	SELL	unknown	ノムラインターナショナルピーエルシー NOMURA INTERNATIONAL PLC	other	-2.8K	¥693	-66.2%	¥22M ($139K)
2023-01-10	SELL	unknown	野村證券株式会社 Nomura Securities Co.,Ltd.	other	196.4K	¥693	-66.2%	¥60M ($385K)
2022-09-21	BUY	unknown	野村アセットマネジメント株式会社 Nomura Asset Management Co., Ltd.	other	236.8K	¥708	+62.7%	¥9M ($57K)
2022-09-21	SELL	unknown	ノムラインターナショナルピーエルシー NOMURA INTERNATIONAL PLC	other	28.0K	¥708	-62.7%	¥24M ($156K)
2022-09-21	SELL	unknown	野村證券株式会社 Nomura Securities Co.,Ltd.	other	282.3K	¥708	-62.7%	¥40M ($261K)
2022-05-09	BUY	Market Buy	野村アセットマネジメント株式会社 Nomura Asset Management Co., Ltd.	other	224.2K	¥508	+126.8%	¥2M ($14K)
2022-05-09	SELL	Market Buy	ノムラインターナショナルピーエルシー NOMURA INTERNATIONAL PLC	other	62.7K	¥508	-126.8%	¥81M ($520K)
2022-05-09	BUY	Market Buy	野村證券株式会社 Nomura Securities Co.,Ltd.	other	338.9K	¥508	+126.8%	¥51M ($326K)
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	219.9K	¥552	+108.7%	¥23M ($151K)
2022-04-06	BUY	unknown	ノムラインターナショナルピーエルシー NOMURA INTERNATIONAL PLC	other	220.7K	¥552	+108.7%	¥117M ($757K)
2022-04-06	SELL	unknown	野村證券株式会社 Nomura Securities Co.,Ltd.	other	239.4K	¥552	-108.7%	¥120M ($776K)
2022-01-07	BUY	Market Buy	野村アセットマネジメント株式会社 Nomura Asset Management Co., Ltd.	other	177.2K	¥547.5	+110.4%	¥1M ($7K)
2022-01-07	SELL	Market Buy	ノムラインターナショナルピーエルシー NOMURA INTERNATIONAL PLC	other	8.0K	¥547.5	-110.4%	¥162M ($1.0M)
2022-01-07	BUY	Market Buy	野村證券株式会社 Nomura Securities Co.,Ltd.	other	457.5K	¥547.5	+110.4%	¥161M ($1.0M)
2021-09-24	BUY	unknown	野村アセットマネジメント株式会社 Nomura Asset Management Co., Ltd.	other	175.5K	¥686.5	+67.8%	¥120M ($777K)
2021-09-24	BUY	unknown	ノムラインターナショナルピーエルシー NOMURA INTERNATIONAL PLC	other	304.6K	¥686.5	+67.8%	¥209M ($1.4M)
2021-09-24	SELL	unknown	野村證券株式会社 Nomura Securities Co.,Ltd.	other	164.2K	¥686.5	-67.8%	¥176M ($1.1M)
2021-07-06	BUY	unknown	野村證券株式会社 Nomura Securities Co.,Ltd.	other	420.2K	¥680	+69.4%	¥286M ($1.8M)
2021-07-06	BUY	unknown	野村アセットマネジメント株式会社 Nomura Asset Management Co., Ltd.	other	175.0K	¥680	+69.4%	¥3M ($18K)
2021-07-06	SELL	unknown	ノムラインターナショナルピーエルシー NOMURA INTERNATIONAL PLC	other	500	¥680	-69.4%	¥295M ($1.9M)
2021-07-06	BUY	Market Buy	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	162.0K	¥680	+69.4%	¥7M ($45K)
2021-07-06	SELL	Market Buy	日興アセットマネジメント株式会社 Nikko Asset Management Co.,Ltd.	other	361.4K	¥680	-69.4%	¥9M ($59K)
2021-03-19	BUY	unknown	ノムラインターナショナルピーエルシー NOMURA INTERNATIONAL PLC	other	432.4K	¥748.983	+53.8%	¥324M ($2.1M)
2021-03-19	BUY	unknown	野村アセットマネジメント株式会社 Nomura Asset Management Co., Ltd.	other	171.0K	¥748.983	+53.8%	¥128M ($826K)

Frequently asked questions

Who has been buying System Support Inc. stock?: 6 distinct investors have filed 15 disclosed large-shareholding filings in System Support Inc. (4396), most recently on 2026-03-23. 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 System Support Inc. have?: System Support Inc. has 15 buy-side and 11 sell-side disclosures on record, covering ¥1.7B ($11.2M) in total reported value, spanning 2021-03-19 to 2026-03-23.
Where does StockDrifts get System Support Inc. 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 System Support Inc.. For how StockDrifts scores these disclosures, see the Japan insider signal tier research, or browse every Japanese stock we track.