Who has been buying JustSystems Corporation stock?

15 distinct investors have filed 41 disclosed large-shareholding filings in JustSystems Corporation (4686), 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 JustSystems Corporation have?

JustSystems Corporation has 41 buy-side and 16 sell-side disclosures on record, covering ¥13.1B ($84.7M) in total reported value, spanning 2022-07-25 to 2026-04-07.

Where does StockDrifts get JustSystems Corporation 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.

JustSystems Corporation 4686

Company

株式会社ジャストシステムJustSystems Corporation

Investors

Buys

Total Value

¥13.1B ($84.7M)

Avg Return

+9.04%

Last Filing

2026-04-07

JustSystems Corporation (4686) has 41 disclosed large-shareholding filings and 16 disclosed disposals on record, filed by 15 distinct investors. Together those filings cover ¥13.1B ($84.7M) in reported transaction value. The earliest filing StockDrifts holds for JustSystems Corporation is dated 2022-07-25; the most recent is 2026-04-07. 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 +9.04%, 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
2026-06-22	BUY	Market Buy	ヒカリ・ツウシン・インベストメンツ・アジア・プライベート・リミテッド Hikari Tsushin Investments Asia Pte. Ltd.	passive	3.2M	¥3,715	+2.4%	¥11.8B ($76.3M)
2026-06-22	BUY	Market Buy	光通信株式会社	passive	2.7M	¥3,715	+2.4%	¥310M ($2.0M)
2026-06-22	BUY	Market Buy	さくら損害保険株式会社	passive	523.9K	¥3,715	+2.4%	¥119M ($770K)
2026-06-22	BUY	Market Buy	株式会社UH7	passive	85.9K	¥3,715	+2.4%	¥319M ($2.1M)
2026-06-22	BUY	Market Buy	株式会社UH6	passive	2.2M	¥3,715	+2.4%	¥8.1B ($52.0M)
2026-06-22	BUY	Market Buy	株式会社UH5	passive	81.6K	¥3,715	+2.4%	¥303M ($2.0M)
2026-06-22	BUY	Market Buy	株式会社アイビー	passive	35.9K	¥3,715	+2.4%	¥133M ($860K)
2026-06-22	BUY	Market Buy	株式会社UH Partners 2	passive	969.1K	¥3,715	+2.4%	¥2.0B ($12.9M)
2026-04-07	BUY	Market Buy	ヒカリ・ツウシン・インベストメンツ・アジア・プライベート・リミテッド Hikari Tsushin Investments Asia Pte. Ltd.	passive	3.2M	¥3,585	+3.2%	¥11.4B ($73.6M)
2026-04-07	BUY	Market Buy	株式会社ザッパラス	passive	85.9K	¥3,585	+3.2%	¥308M ($2.0M)
2026-04-07	BUY	Market Buy	さくら損害保険株式会社	passive	496.1K	¥3,585	+3.2%	¥1.8B ($11.5M)
2026-04-07	BUY	Market Buy	株式会社UH6	passive	2.2M	¥3,585	+3.2%	¥7.8B ($50.2M)
2026-04-07	BUY	Market Buy	株式会社UH5	passive	81.6K	¥3,585	+3.2%	¥293M ($1.9M)
2026-04-07	BUY	Market Buy	株式会社アイビー	passive	35.9K	¥3,585	+3.2%	¥129M ($830K)
2026-04-07	SELL	Market Buy	株式会社UH Partners 2	passive	429.3K	¥3,585	-3.2%	¥7.0B ($45.2M)
2026-04-07	BUY	Market Buy	光通信株式会社	passive	2.6M	¥3,585	+3.2%	¥322M ($2.1M)
2026-03-12	BUY	Market Buy	ヒカリ・ツウシン・インベストメンツ・アジア・プライベート・リミテッド Hikari Tsushin Investments Asia Pte. Ltd.	passive	3.2M	¥3,545	-2.0%	¥11.5B ($74.2M)
2026-03-12	BUY	Market Buy	株式会社ザッパラス	passive	85.9K	¥3,545	-2.0%	¥311M ($2.0M)
2026-03-12	BUY	Market Buy	さくら損害保険株式会社	passive	496.1K	¥3,545	+2.0%	¥1.8B ($11.6M)
2026-03-12	BUY	Market Buy	株式会社UH5	passive	81.6K	¥3,545	-2.0%	¥295M ($1.9M)
2026-03-12	SELL	Market Buy	株式会社アイビー	passive	35.9K	¥3,545	-2.0%	¥130M ($837K)
2026-03-12	BUY	Market Buy	株式会社UH Partners 2	passive	2.4M	¥3,545	+2.0%	¥8.6B ($55.6M)
2026-03-12	BUY	Market Buy	光通信株式会社	passive	2.6M	¥3,545	+2.0%	¥9.2B ($59.6M)
2025-09-26	BUY	Market Buy	ヒカリ・ツウシン・インベストメンツ・アジア・プライベート・リミテッド Hikari Tsushin Investments Asia Pte. Ltd.	passive	3.2M	¥4,775	-24.3%	¥15.2B ($98.0M)
2025-09-26	BUY	Market Buy	株式会社ザッパラス Zappalas Co., Ltd.	passive	85.9K	¥4,775	-24.3%	¥410M ($2.6M)
2025-09-26	BUY	Market Buy	さくら損害保険株式会社 Sakura General Insurance Co., Ltd.	passive	392.5K	¥4,775	-24.3%	¥92M ($594K)
2025-09-26	BUY	Market Buy	株式会社アイビー IB, Inc.	passive	76.3K	¥4,775	-24.3%	¥364M ($2.4M)
2025-09-26	BUY	Market Buy	株式会社UH Partners 2 UH Partners 2, Inc.	passive	2.0M	¥4,775	-24.3%	¥552M ($3.6M)
2025-09-26	BUY	Market Buy	光通信株式会社 Hikari Tsushin K.K.	passive	2.4M	¥4,775	-24.3%	¥11.6B ($75.1M)
2025-09-02	BUY	Market Buy	ヒカリ・ツウシン・インベストメンツ・アジア・プライベート・リミテッド Hikari Tsushin Investments Asia Pte. Ltd.	passive	3.2M	¥4,585	-21.2%	¥14.6B ($94.1M)
2025-09-02	BUY	Market Buy	株式会社ザッパラス Zappalas Co., Ltd.	passive	85.9K	¥4,585	-21.2%	¥394M ($2.5M)
2025-09-02	BUY	Market Buy	さくら損害保険株式会社 Sakura General Insurance Co., Ltd.	passive	371.2K	¥4,585	-21.2%	¥501M ($3.2M)
2025-09-02	BUY	Market Buy	株式会社アイビー IB, Inc.	passive	76.3K	¥4,585	-21.2%	¥350M ($2.3M)
2025-09-02	BUY	Market Buy	株式会社UH Partners 2 UH Partners 2, Inc.	passive	1.9M	¥4,585	-21.2%	¥2.1B ($13.9M)
2025-09-02	BUY	Market Buy	光通信株式会社 Hikari Tsushin K.K.	passive	2.4M	¥4,585	-21.2%	¥11.2B ($72.1M)
2025-07-08	BUY	Market Buy	ヒカリ・ツウシン・インベストメンツ・アジア・プライベート・リミテッド Hikari Tsushin Investments Asia Pte. Ltd.	passive	3.2M	¥3,660	-1.2%	¥11.6B ($75.2M)
2025-07-08	BUY	Market Buy	株式会社ザッパラス Zappalas Co., Ltd.	passive	85.9K	¥3,660	-1.2%	¥314M ($2.0M)
2025-07-08	BUY	Market Buy	さくら損害保険株式会社 Sakura General Insurance Co., Ltd.	passive	265.0K	¥3,660	-1.2%	¥47M ($303K)
2025-07-08	BUY	Market Buy	光通信株式会社 Hikari Tsushin K.K.	passive	2.4M	¥3,660	-1.2%	¥8.9B ($57.6M)
2025-07-08	BUY	Market Buy	株式会社UH Partners 2 UH Partners 2, Inc.	passive	1.4M	¥3,660	-1.2%	¥2.3B ($15.0M)
2025-05-19	BUY	Market Buy	株式会社ザッパラス Zappalas Co., Ltd.	passive	85.9K	¥3,400	+6.3%	¥292M ($1.9M)
2025-05-19	BUY	Market Buy	さくら損害保険株式会社 Sakura General Insurance Co., Ltd.	passive	250.7K	¥3,400	+6.3%	¥175M ($1.1M)
2025-05-19	BUY	Market Buy	ヒカリ・ツウシン・インベストメンツ・アジア・プライベート・リミテッド Hikari Tsushin Investments Asia Pte. Ltd.	passive	3.2M	¥3,400	+6.3%	¥10.8B ($69.8M)
2025-05-19	BUY	Market Buy	株式会社UH Partners 2 UH Partners 2, Inc.	passive	753.0K	¥3,400	+6.3%	¥1.6B ($10.3M)
2025-05-19	BUY	Market Buy	光通信株式会社 Hikari Tsushin K.K.	passive	2.4M	¥3,400	+6.3%	¥153M ($986K)
2024-12-20	BUY	Market Buy	ヒカリ・ツウシン・インベストメンツ・アジア・プライベート・リミテッド Hikari Tsushin Investments Asia Pte. Ltd.	passive	3.2M	¥3,550	+1.8%	¥11.3B ($72.9M)
2024-12-20	BUY	Market Buy	さくら損害保険株式会社 Sakura General Insurance Co., Ltd.	passive	200.5K	¥3,550	+1.8%	¥182M ($1.2M)
2024-12-20	BUY	Market Buy	光通信株式会社 Hikari Tsushin K.K.	passive	2.4M	¥3,550	+1.8%	¥1.1B ($7.1M)
2024-12-20	BUY	Market Buy	株式会社UH Partners 2 UH Partners 2, Inc.	passive	282.9K	¥3,550	+1.8%	¥1.0B ($6.5M)
2024-12-02	SELL	negotiated	浮川初子 Hatsuko Ukikawa	strategic	1.5M	¥3,500	-3.3%	¥67M ($435K)

Showing the 50 most recent of 106 filings.

Frequently asked questions

Who has been buying JustSystems Corporation stock?: 15 distinct investors have filed 41 disclosed large-shareholding filings in JustSystems Corporation (4686), 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 JustSystems Corporation have?: JustSystems Corporation has 41 buy-side and 16 sell-side disclosures on record, covering ¥13.1B ($84.7M) in total reported value, spanning 2022-07-25 to 2026-04-07.
Where does StockDrifts get JustSystems Corporation 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 JustSystems Corporation. For how StockDrifts scores these disclosures, see the Japan insider signal tier research, or browse every Japanese stock we track.