Who has been buying Software Service, Inc. stock?

6 distinct investors have filed 6 disclosed large-shareholding filings in Software Service, Inc. (3733), most recently on 2026-04-07. 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 Software Service, Inc. have?

Software Service, Inc. has 6 buy-side and 11 sell-side disclosures on record, covering ¥10.2B ($65.9M) in total reported value, spanning 2021-04-01 to 2026-04-07.

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.

Software Service, Inc. 3733

Company

株式会社ソフトウェア・サービスSoftware Service, Inc.

Investors

Buys

Total Value

¥10.2B ($65.9M)

Avg Return

+19.81%

Last Filing

2026-04-07

Software Service, Inc. (3733) has 6 disclosed large-shareholding filings and 11 disclosed disposals on record, filed by 6 distinct investors. Together those filings cover ¥10.2B ($65.9M) in reported transaction value. The earliest filing StockDrifts holds for Software Service, Inc. is dated 2021-04-01; the most recent is 2026-04-07. Across these filings the average return since disclosure is +19.81%, 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
2026-10-27	BUY	unknown	宮﨑勝	unknown	0	¥11,750	-	-
2026-10-27	BUY	Market Buy	株式会社エム・エムホールディングス	strategic	827.2K	¥11,750	-0.6%	¥2.7B ($17.2M)
2026-10-27	SELL	unknown	宮崎勝	activist	0	¥11,750	+0.6%	¥2.7B ($17.2M)
2026-08-07	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	148.5K	¥11,350	-	-
2026-08-07	BUY	unknown	エフアイエーエムエルエルシー FIAM LLC	other	206.8K	¥11,350	-	-
2026-08-07	BUY	unknown	フィデリティマネジメントトラストカンパニー Fidelity Management Trust Company	other	8.5K	¥11,350	-	-
2026-08-07	SELL	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	37.2K	¥11,350	-2.9%	¥1.6B ($10.1M)
2026-07-30	SELL	unknown	宮崎勝	activist	227.2K	¥11,390	-2.5%	¥3.3B ($21.3M)
2026-07-30	BUY	unknown	株式会社エム・エムホールディングス	strategic	309.5K	¥11,390	-	-
2026-07-30	BUY	unknown	宮﨑勝	unknown	227.2K	¥11,390	-	¥2.6B ($16.7M)
2026-07-30	BUY	Market Buy	株式会社エム・エムホールディングス	strategic	600.0K	¥11,390	+2.5%	¥3.3B ($21.3M)
2026-07-30	SELL	unknown	宮崎勝	activist	517.7K	¥11,390	-2.5%	¥3.2B ($20.8M)
2026-07-30	BUY	unknown	宮﨑勝	unknown	517.7K	¥11,390	-	¥5.9B ($38.0M)
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	148.5K	¥10,100	-15.6%	¥2.3B ($14.6M)
2026-07-23	BUY	Market Buy	エフアイエーエムエルエルシー FIAM LLC	other	206.8K	¥10,100	+15.6%	¥754M ($4.9M)
2026-07-23	BUY	unknown	フィデリティマネジメントトラストカンパニー Fidelity Management Trust Company	other	8.5K	¥10,100	-	-
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	175.4K	¥10,100	-	¥1.8B ($11.4M)
2026-06-16	BUY	unknown	フィデリティマネジメントトラストカンパニー Fidelity Management Trust Company	other	7.1K	¥10,240	-	-
2026-06-16	BUY	unknown	エフエムアールエルエルシー(FMR LLC) FMR LLC	other	463.4K	¥10,240	-	¥584M ($3.8M)
2026-06-16	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	416.3K	¥10,240	-14.1%	¥478M ($3.1M)
2026-06-16	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	372.0K	¥10,240	-	-
2026-06-16	BUY	Market Buy	エフアイエーエムエルエルシー FIAM LLC	other	132.0K	¥10,240	+14.1%	¥6M ($36K)
2026-06-16	BUY	unknown	フィデリティマネジメントトラストカンパニー Fidelity Management Trust Company	other	8.2K	¥10,240	-	-
2026-06-16	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	372.0K	¥10,240	+14.1%	¥11M ($73K)
2026-06-16	BUY	Market Buy	エフアイエーエムエルエルシー FIAM LLC	other	132.0K	¥10,240	+14.1%	¥11M ($73K)
2026-06-16	BUY	Market Buy	フィデリティマネジメントトラストカンパニー Fidelity Management Trust Company	other	8.2K	¥10,240	+14.1%	¥11M ($73K)
2026-06-16	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	370.8K	¥10,240	+14.1%	¥202M ($1.3M)
2026-06-16	BUY	Market Buy	エフアイエーエムエルエルシー FIAM LLC	other	130.6K	¥10,240	+14.1%	¥410M ($2.6M)
2026-06-16	BUY	Market Buy	エフアイエーエムエルエルシー FIAM LLC	other	90.5K	¥10,240	+14.1%	¥270M ($1.7M)
2026-06-16	BUY	unknown	フィデリティマネジメントトラストカンパニー Fidelity Management Trust Company	other	7.0K	¥10,240	-	-
2026-06-16	BUY	unknown	エフアイエーエムエルエルシー FIAM LLC	other	64.1K	¥10,240	-	¥656M ($4.2M)
2026-06-16	BUY	unknown	フィデリティマネジメントトラストカンパニー Fidelity Management Trust Company	other	7.0K	¥10,240	-	¥72M ($462K)
2026-06-16	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) Fidelity Management & Research Company LLC	corporate	463.4K	¥10,240	-14.1%	¥584M ($3.8M)
2026-06-16	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	351.0K	¥10,240	-14.1%	¥669M ($4.3M)
2026-04-07	SELL	unknown	みずほ証券株式会社	unknown	0	¥11,590	-0.8%	¥5.4B ($35.1M)
2026-04-07	SELL	unknown	アセットマネジメントOne株式会社	unknown	0	¥11,590	-0.8%	¥216M ($1.4M)
2026-03-26	BUY	unknown	株式会社エム・エムホールディングス	strategic	309.5K	¥12,050	-3.1%	¥2.5B ($16.3M)
2026-03-26	BUY	unknown	宮﨑勝	unknown	800.0K	¥12,050	-	¥9.6B ($62.2M)
2026-03-26	SELL	unknown	宮崎勝	activist	800.0K	¥12,050	+3.1%	¥2.5B ($16.3M)
2026-03-24	SELL	unknown	宮崎勝	activist	1.0M	¥11,860	+1.5%	¥3.4B ($22.3M)
2026-03-24	BUY	unknown	株式会社エム・エムホールディングス	strategic	100.0K	¥11,860	-	-
2026-03-24	BUY	unknown	宮﨑勝	unknown	1.0M	¥11,860	-	¥12.0B ($77.2M)
2026-02-02	BUY	unknown	株式会社エム・エムホールディングス	strategic	100.0K	¥12,870	-	-
2026-02-02	BUY	unknown	宮﨑勝	unknown	1.3M	¥12,870	-	¥16.7B ($107.9M)
2026-02-02	BUY	unknown	宮崎勝	activist	1.3M	¥12,870	-	-
2026-01-19	BUY	unknown	宮﨑勝	unknown	1.3M	¥13,850	-	¥18.0B ($116.2M)
2026-01-19	BUY	unknown	宮崎勝	activist	1.3M	¥13,850	-	-
2026-01-19	BUY	unknown	株式会社エム・エムホールディングス	strategic	100.0K	¥13,850	-	-
2025-11-21	BUY	unknown	エフエムアールエルエルシー(FMR LLC) FMR LLC	other	512.2K	¥14,180	-	-
2025-11-21	BUY	unknown	エフエムアールエルエルシー(FMR LLC) FMR LLC	other	512.2K	¥14,180	-	-

Showing the 50 most recent of 166 filings.

Frequently asked questions

Who has been buying Software Service, Inc. stock?: 6 distinct investors have filed 6 disclosed large-shareholding filings in Software Service, Inc. (3733), most recently on 2026-04-07. 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 Software Service, Inc. have?: Software Service, Inc. has 6 buy-side and 11 sell-side disclosures on record, covering ¥10.2B ($65.9M) in total reported value, spanning 2021-04-01 to 2026-04-07.
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.