Who has been buying KOMATSU MATERE Co.,Ltd. stock?

4 distinct investors have filed 6 disclosed large-shareholding filings in KOMATSU MATERE Co.,Ltd. (3580), most recently on 2026-04-06. 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 KOMATSU MATERE Co.,Ltd. have?

KOMATSU MATERE Co.,Ltd. has 6 buy-side and 5 sell-side disclosures on record, covering ¥682M ($4.4M) in total reported value, spanning 2022-03-22 to 2026-04-06.

Where does StockDrifts get KOMATSU MATERE 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.

KOMATSU MATERE Co.,Ltd. 3580

Company

小松マテーレ株式会社KOMATSU MATERE Co.,Ltd.

Investors

Buys

Total Value

¥682M ($4.4M)

Avg Return

-19.35%

Last Filing

2026-04-06

KOMATSU MATERE Co.,Ltd. (3580) has 6 disclosed large-shareholding filings and 5 disclosed disposals on record, filed by 4 distinct investors. Together those filings cover ¥682M ($4.4M) in reported transaction value. The earliest filing StockDrifts holds for KOMATSU MATERE Co.,Ltd. is dated 2022-03-22; the most recent is 2026-04-06. 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 -19.35%, 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
2026-07-16	SELL	Market Buy	シンフォニー・フィナンシャル・パートナーズ(シンガポール)ピーティーイー・リミテッド(Symphony Financial Partners (Singapore) Pte. Ltd.) Symphony Financial Partners (Singapore) Pte. Ltd.	activist	5.1M	¥727	-4.0%	¥297M ($1.9M)
2026-04-06	BUY	negotiated	アモーヴァ・アセットマネジメント株式会社	other	431.7K	¥791	-6.5%	¥3M ($20K)
2026-04-06	SELL	negotiated	三井住友トラスト・アセットマネジメント株式会社	other	478.6K	¥791	+6.5%	¥62M ($401K)
2026-04-06	SELL	negotiated	三井住友信託銀行株式会社	strategic	730.0K	¥791	+6.5%	¥307M ($2.0M)
2026-03-13	BUY	Market Buy	シンフォニー・フィナンシャル・パートナーズ(シンガポール)ピーティーイー・リミテッド(Symphony Financial Partners (Singapore) Pte. Ltd.) Symphony Financial Partners (Singapore) Pte. Ltd.	activist	5.5M	¥826	-6.8%	¥425M ($2.7M)
2025-10-17	BUY	Market Buy	シンフォニー・フィナンシャル・パートナーズ(シンガポール)ピーティーイー・リミテッド(Symphony Financial Partners (Singapore) Pte. Ltd.) Symphony Financial Partners (Singapore) Pte. Ltd.	activist	5.5M	¥818	-5.9%	¥219M ($1.4M)
2025-09-19	SELL	negotiated	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	611.6K	¥860	+10.5%	¥249M ($1.6M)
2025-09-19	BUY	negotiated	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	469.1K	¥860	-10.5%	¥403M ($2.6M)
2025-09-19	BUY	negotiated	三井住友信託銀行株式会社 Sumitomo Mitsui Trust Bank,Limited	strategic	1.2M	¥860	-10.5%	¥1.1B ($6.8M)
2023-11-21	BUY	Market Buy	シンフォニー・フィナンシャル・パートナーズ(シンガポール)ピーティーイー・リミテッド(Symphony Financial Partners (Singapore) Pte. Ltd.) Symphony Financial Partners (Singapore) Pte. Ltd.	activist	5.2M	¥803	-4.1%	¥353M ($2.3M)
2023-04-04	SELL	Market Buy	シンフォニー・フィナンシャル・パートナーズ(シンガポール)ピーティーイー・リミテッド(Symphony Financial Partners (Singapore) Pte. Ltd.) Symphony Financial Partners (Singapore) Pte. Ltd.	activist	4.8M	¥696	-10.6%	¥312M ($2.0M)
2022-06-28	SELL	Market Buy	シンフォニー・フィナンシャル・パートナーズ(シンガポール)ピーティーイー・リミテッド(Symphony Financial Partners (Singapore) Pte. Ltd.) Symphony Financial Partners (Singapore) Pte. Ltd.	activist	5.2M	¥1,178	+34.6%	¥513M ($3.3M)
2022-03-22	BUY	negotiated	三井住友信託銀行株式会社 Sumitomo Mitsui Trust Bank,Limited	strategic	1.2M	¥1,438	-46.5%	¥1.8B ($11.4M)
2022-03-22	BUY	negotiated	日興アセットマネジメント株式会社 Nikko Asset Management Co.,Ltd.	other	468.3K	¥1,438	-46.5%	¥254M ($1.6M)
2022-03-22	BUY	negotiated	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	901.9K	¥1,438	-46.5%	¥385M ($2.5M)

Frequently asked questions

Who has been buying KOMATSU MATERE Co.,Ltd. stock?: 4 distinct investors have filed 6 disclosed large-shareholding filings in KOMATSU MATERE Co.,Ltd. (3580), most recently on 2026-04-06. 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 KOMATSU MATERE Co.,Ltd. have?: KOMATSU MATERE Co.,Ltd. has 6 buy-side and 5 sell-side disclosures on record, covering ¥682M ($4.4M) in total reported value, spanning 2022-03-22 to 2026-04-06.
Where does StockDrifts get KOMATSU MATERE 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 KOMATSU MATERE Co.,Ltd.. For how StockDrifts scores these disclosures, see the Japan insider signal tier research, or browse every Japanese stock we track.