Who has been buying Fixstars Corporation stock?

15 distinct investors have filed 32 disclosed large-shareholding filings in Fixstars Corporation (3687), 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 Fixstars Corporation have?

Fixstars Corporation has 32 buy-side and 30 sell-side disclosures on record, covering ¥24.3B ($157.1M) in total reported value, spanning 2021-10-07 to 2026-04-22.

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.

Fixstars Corporation 3687

Company

株式会社フィックスターズFixstars Corporation

Investors

Buys

Total Value

¥24.3B ($157.1M)

Avg Return

+8.93%

Last Filing

2026-04-22

Fixstars Corporation (3687) has 32 disclosed large-shareholding filings and 30 disclosed disposals on record, filed by 15 distinct investors. Together those filings cover ¥24.3B ($157.1M) in reported transaction value. The earliest filing StockDrifts holds for Fixstars Corporation is dated 2021-10-07; the most recent is 2026-04-22. Across these filings the average return since disclosure is +8.93%, 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
2026-09-24	BUY	Market Buy	アモーヴァ・アセットマネジメント株式会社	other	404.6K	¥2,243	-0.9%	¥15M ($97K)
2026-09-24	SELL	unknown	三井住友トラスト・アセットマネジメント株式会社	other	545.6K	¥2,243	+0.9%	¥543M ($3.5M)
2026-09-24	BUY	unknown	三井住友信託銀行株式会社	other	800.0K	¥2,243	-	-
2026-06-10	SELL	unknown	グッドハートパートナーズエルエルピー(Goodhart Partners LLP) Goodhart Partners LLP	other	1.4M	¥2,387	+6.9%	¥1.0B ($6.5M)
2026-06-08	SELL	unknown	グッドハートパートナーズエルエルピー(Goodhart Partners LLP) Goodhart Partners LLP	other	1.8M	¥2,935	+24.3%	¥1.5B ($9.4M)
2026-06-04	SELL	unknown	グッドハートパートナーズエルエルピー(Goodhart Partners LLP) Goodhart Partners LLP	other	2.3M	¥3,200	+30.6%	¥2.0B ($12.9M)
2026-04-22	BUY	Market Buy	みずほ証券株式会社	other	532.8K	¥1,310	+69.6%	¥13M ($85K)
2026-04-22	SELL	unknown	アセットマネジメントOne株式会社	other	1.0M	¥1,310	-69.6%	¥648M ($4.2M)
2026-04-02	SELL	unknown	グッドハートパートナーズエルエルピー(Goodhart Partners LLP) Goodhart Partners LLP	other	2.9M	¥1,206	-84.3%	¥466M ($3.0M)
2026-02-06	BUY	Market Buy	みずほ証券株式会社 Mizuho Securities Co., Ltd.	other	2.0M	¥1,442	+54.1%	¥10M ($63K)
2026-01-22	BUY	unknown	みずほ証券株式会社	other	532.8K	¥1,572	+41.4%	¥838M ($5.4M)
2026-01-22	BUY	unknown	アセットマネジメントOne株式会社	other	1.5M	¥1,572	+41.4%	¥2.3B ($15.1M)
2026-01-16	SELL	unknown	グッドハートパートナーズエルエルピー(Goodhart Partners LLP) Goodhart Partners LLP	other	3.3M	¥1,635	-35.9%	¥588M ($3.8M)
2025-12-23	SELL	unknown	グッドハートパートナーズエルエルピー(Goodhart Partners LLP) Goodhart Partners LLP	other	3.7M	¥1,582	-40.5%	¥660M ($4.3M)
2025-09-19	BUY	Market Buy	三井住友信託銀行株式会社 Sumitomo Mitsui Trust Bank,Limited	other	800.0K	¥1,916	-	-
2025-09-19	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	785.9K	¥1,916	+16.0%	¥271M ($1.7M)
2025-09-19	BUY	Market Buy	アモーヴァ・アセットマネジメント株式会社 Amova Asset Management Co., Ltd.	other	397.8K	¥1,916	+16.0%	¥193M ($1.2M)
2025-09-05	SELL	unknown	アセットマネジメントOne株式会社 Asset Management One Co., Ltd.	other	1.6M	¥1,739	-27.8%	¥655M ($4.2M)
2025-08-29	SELL	unknown	三木聡 Satoshi Miki	activist	3.1M	¥1,903	-16.8%	¥384M ($2.5M)
2025-08-29	BUY	unknown	株式会社グリーンテック Green Tech Co., Ltd.	activist	200.0K	¥1,903	-	-
2025-08-29	BUY	unknown	株式会社ANES ANES Co., Ltd.	activist	200.0K	¥1,903	-	-
2025-06-06	SELL	unknown	長谷川智彦 Tomohiko Hasegawa	other	2.1M	¥2,020	-10.0%	¥1.1B ($7.3M)
2025-02-19	SELL	unknown	三木聡 Satoshi Miki	activist	3.3M	¥1,917	-15.9%	¥277M ($1.8M)
2025-02-19	SELL	unknown	株式会社グリーンテック Green Tech Co., Ltd.	activist	200.0K	¥1,917	-15.9%	¥193M ($1.2M)
2025-02-19	SELL	unknown	株式会社ANES ANES Co., Ltd.	activist	200.0K	¥1,917	-15.9%	¥193M ($1.2M)
2025-02-07	SELL	unknown	アセットマネジメントOne株式会社 Asset Management One Co., Ltd.	other	2.0M	¥1,980	-12.2%	¥1.2B ($8.0M)
2025-02-07	SELL	unknown	みずほ証券株式会社 Mizuho Securities Co., Ltd.	other	26.1K	¥1,980	-12.2%	¥53M ($344K)
2025-01-22	SELL	unknown	アセットマネジメントOne株式会社 Asset Management One Co., Ltd.	other	2.6M	¥1,712	-29.8%	¥184M ($1.2M)
2025-01-22	SELL	unknown	みずほ証券株式会社 Mizuho Securities Co., Ltd.	other	52.9K	¥1,712	-29.8%	¥236M ($1.5M)
2024-11-15	SELL	unknown	グッドハートパートナーズエルエルピー(Goodhart Partners LLP) Goodhart Partners LLP	other	4.1M	¥1,614	-37.7%	¥608M ($3.9M)
2024-10-04	BUY	Market Buy	三井住友信託銀行株式会社 Sumitomo Mitsui Trust Bank,Limited	other	800.0K	¥1,537	-	-
2024-10-04	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	644.5K	¥1,537	+44.6%	¥114M ($734K)
2024-10-04	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	297.5K	¥1,537	-44.6%	¥41M ($267K)
2024-07-17	BUY	Market Buy	グッドハートパートナーズエルエルピー(Goodhart Partners LLP) Goodhart Partners LLP	other	4.5M	¥1,975	+12.5%	¥691M ($4.5M)
2024-07-02	BUY	Market Buy	グッドハートパートナーズエルエルピー(Goodhart Partners LLP) Goodhart Partners LLP	other	4.1M	¥1,928	+15.3%	¥674M ($4.4M)
2024-06-18	BUY	Market Buy	グッドハートパートナーズエルエルピー(Goodhart Partners LLP) Goodhart Partners LLP	other	3.8M	¥1,938	+14.7%	¥717M ($4.6M)
2024-04-22	SELL	unknown	三木聡 Satoshi Miki	activist	3.4M	¥1,997	-11.3%	¥450M ($2.9M)
2024-04-22	BUY	unknown	アセットマネジメントOne株式会社 Asset Management One Co., Ltd.	other	2.7M	¥1,997	+11.3%	¥5.4B ($34.7M)
2024-04-22	BUY	unknown	みずほ証券株式会社 Mizuho Securities Co., Ltd.	other	191.7K	¥1,997	-	-
2024-04-22	SELL	unknown	アセットマネジメントOneインターナショナル Asset Management One International Ltd.	other	31.3K	¥1,997	-11.3%	¥20M ($130K)
2024-04-22	BUY	unknown	株式会社グリーンテック Green Tech Co., Ltd.	activist	300.0K	¥1,997	-	-
2024-04-22	BUY	unknown	株式会社ANES ANES Co., Ltd.	activist	300.0K	¥1,997	-	-
2024-04-02	SELL	unknown	原行範 Yukinori Hara	strategic	1.4M	¥2,262	+1.8%	¥905M ($5.8M)
2024-03-19	BUY	unknown	アセットマネジメントOneインターナショナル Asset Management One International Ltd.	other	40.0K	¥2,261	-	-
2024-03-19	BUY	unknown	アセットマネジメントOne株式会社 Asset Management One Co., Ltd.	other	3.1M	¥2,261	-1.7%	¥6.9B ($44.5M)
2024-03-19	BUY	unknown	みずほ証券株式会社 Mizuho Securities Co., Ltd.	other	190.6K	¥2,261	-	¥431M ($2.8M)
2024-03-18	BUY	Market Buy	グッドハートパートナーズエルエルピー(Goodhart Partners LLP) Goodhart Partners LLP	other	3.4M	¥2,268	-2.0%	¥1.1B ($7.2M)
2024-02-29	SELL	unknown	原行範 Yukinori Hara	strategic	1.7M	¥1,925	-15.4%	¥1.0B ($6.5M)
2024-02-29	BUY	unknown	原行範 Yukinori Hara	strategic	1.8M	¥1,925	-	¥809M ($5.2M)
2024-02-02	BUY	Market Buy	グッドハートパートナーズエルエルピー(Goodhart Partners LLP) Goodhart Partners LLP	other	2.9M	¥1,692	+31.3%	¥797M ($5.1M)

Showing the 50 most recent of 90 filings.

Frequently asked questions

Who has been buying Fixstars Corporation stock?: 15 distinct investors have filed 32 disclosed large-shareholding filings in Fixstars Corporation (3687), 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 Fixstars Corporation have?: Fixstars Corporation has 32 buy-side and 30 sell-side disclosures on record, covering ¥24.3B ($157.1M) in total reported value, spanning 2021-10-07 to 2026-04-22.
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.