Who has been buying Kuramoto Co., Ltd. stock?

4 distinct investors have filed 8 disclosed large-shareholding filings in Kuramoto Co., Ltd. (5216), 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 Kuramoto Co., Ltd. have?

Kuramoto Co., Ltd. has 8 buy-side and 4 sell-side disclosures on record, covering ¥2.2B ($14.0M) in total reported value, spanning 2021-09-09 to 2026-04-06.

Where does StockDrifts get Kuramoto 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.

Kuramoto Co., Ltd. 5216

Company

株式会社倉元製作所Kuramoto Co., Ltd.

Investors

Buys

Total Value

¥2.2B ($14.0M)

Avg Return

-22.36%

Last Filing

2026-04-06

Kuramoto Co., Ltd. (5216) has 8 disclosed large-shareholding filings and 4 disclosed disposals on record, filed by 4 distinct investors. Together those filings cover ¥2.2B ($14.0M) in reported transaction value. The earliest filing StockDrifts holds for Kuramoto Co., Ltd. is dated 2021-09-09; 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 -22.36%, 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
2026-07-08	BUY	Market Buy	Ample Harvest Capital (Hong Kong) Limited	passive	3.4M	¥151	+1.3%	¥516M ($3.3M)
2026-04-06	BUY	Market Buy	那須マテリアル株式会社 NASU MATERIAL INC.	passive	4.6M	¥167	-9.0%	¥89M ($576K)
2026-04-03	BUY	Market Buy	光博有限公司(Prolight Corporation Limited) Prolight Corporation Limited	other	15.4M	¥167	-9.0%	¥181M ($1.2M)
2026-01-23	SELL	unknown	王馳 WANG CHI	other	6.4M	¥208	+15.9%	¥109M ($702K)
2025-08-07	BUY	unknown	光博有限公司(Prolight Corporation Limited) Prolight Corporation Limited	other	13.3M	¥217	-19.4%	¥2.9B ($18.6M)
2025-08-07	BUY	unknown	光博有限公司(Prolight Corporation Limited) Prolight Corporation Limited	other	13.3M	¥217	-19.4%	¥2.9B ($18.6M)
2025-05-07	BUY	unknown	光博有限公司(Prolight Corporation Limited) Prolight Corporation Limited	other	13.3M	¥265	-34.0%	¥3.5B ($22.7M)
2025-05-07	BUY	unknown	光博有限公司(Prolight Corporation Limited) Prolight Corporation Limited	other	13.3M	¥265	-34.0%	¥3.5B ($22.7M)
2025-04-21	BUY	Market Buy	渡邉敏行 TOSHIYUKI WATANABE	passive	7.2M	¥241	-27.4%	¥143M ($925K)
2025-03-17	BUY	unknown	光博有限公司(Prolight Corporation Limited) Prolight Corporation Limited	other	13.3M	¥242	-27.7%	¥3.2B ($20.7M)
2025-03-17	BUY	unknown	光博有限公司(Prolight Corporation Limited) Prolight Corporation Limited	other	13.3M	¥242	-27.7%	¥8M ($52K)
2025-03-17	BUY	unknown	光博有限公司(Prolight Corporation Limited) Prolight Corporation Limited	other	13.3M	¥242	-27.7%	¥8M ($52K)
2025-01-20	BUY	unknown	光博有限公司(Prolight Corporation Limited) Prolight Corporation Limited	other	13.3M	¥218	-19.7%	¥2.9B ($18.7M)
2025-01-20	BUY	unknown	光博有限公司(Prolight Corporation Limited) Prolight Corporation Limited	other	13.3M	¥218	-19.7%	¥565M ($3.6M)
2025-01-20	BUY	unknown	光博有限公司(Prolight Corporation Limited) Prolight Corporation Limited	other	13.3M	¥218	-19.7%	¥565M ($3.6M)
2024-11-18	BUY	unknown	光博有限公司(Prolight Corporation Limited) Prolight Corporation Limited	other	13.3M	¥219	-20.1%	¥2.9B ($18.8M)
2024-11-05	BUY	unknown	王馳 WANG CHI	other	6.9M	¥256	-31.6%	¥1.8B ($11.4M)
2024-11-05	BUY	Market Buy	那須マテリアル株式会社 NASU MATERIAL INC.	passive	3.1M	¥256	-31.6%	¥115M ($739K)
2024-11-05	BUY	Market Buy	那須マテリアル株式会社 NASU MATERIAL INC.	passive	3.1M	¥256	-31.6%	¥115M ($739K)
2024-11-05	SELL	unknown	光博有限公司(Prolight Corporation Limited) Prolight Corporation Limited	other	13.3M	¥256	+31.6%	¥310M ($2.0M)
2024-07-24	BUY	Market Buy	渡邉敏行 TOSHIYUKI WATANABE	passive	1.2M	¥441	-60.3%	¥528M ($3.4M)
2024-07-24	BUY	Market Buy	渡邉敏行 TOSHIYUKI WATANABE	passive	1.2M	¥441	-60.3%	¥528M ($3.4M)
2024-07-24	BUY	Market Buy	渡邉敏行 TOSHIYUKI WATANABE	passive	1.2M	¥441	-60.3%	¥528M ($3.4M)
2024-07-24	BUY	Market Buy	渡邉敏行 TOSHIYUKI WATANABE	passive	1.2M	¥441	-60.3%	¥528M ($3.4M)
2024-07-24	BUY	Market Buy	渡邉敏行 TOSHIYUKI WATANABE	passive	1.2M	¥441	-60.3%	¥528M ($3.4M)
2024-07-05	SELL	unknown	光博有限公司(Prolight Corporation Limited) Prolight Corporation Limited	other	13.3M	¥427	+59.0%	¥213M ($1.4M)
2024-07-05	SELL	unknown	光博有限公司(Prolight Corporation Limited) Prolight Corporation Limited	other	12.8M	¥427	+59.0%	¥213M ($1.4M)
2024-07-05	BUY	unknown	光博有限公司(Prolight Corporation Limited) Prolight Corporation Limited	other	13.3M	¥427	-59.0%	¥213M ($1.4M)
2024-07-05	BUY	unknown	光博有限公司(Prolight Corporation Limited) Prolight Corporation Limited	other	12.8M	¥427	-59.0%	¥213M ($1.4M)
2024-07-04	BUY	unknown	光博有限公司(Prolight Corporation Limited) Prolight Corporation Limited	other	13.8M	¥399	-56.1%	¥1.4B ($9.0M)
2024-07-04	BUY	unknown	光博有限公司(Prolight Corporation Limited) Prolight Corporation Limited	other	13.8M	¥399	-56.1%	¥1.4B ($9.0M)
2024-07-04	BUY	unknown	光博有限公司(Prolight Corporation Limited) Prolight Corporation Limited	other	13.8M	¥399	-56.1%	¥1.4B ($9.0M)
2024-07-04	BUY	unknown	光博有限公司(Prolight Corporation Limited) Prolight Corporation Limited	other	13.8M	¥399	-56.1%	¥1.4B ($9.0M)
2024-04-16	BUY	Market Buy	渡邉敏行 TOSHIYUKI WATANABE	passive	1.2M	¥233	-24.9%	¥279M ($1.8M)
2024-04-16	BUY	Market Buy	渡邉敏行 TOSHIYUKI WATANABE	passive	1.2M	¥233	-24.9%	¥279M ($1.8M)
2021-09-09	BUY	Market Buy	那須マテリアル株式会社 NASU MATERIAL INC.	passive	2.3M	¥158	+10.8%	¥368M ($2.4M)

Frequently asked questions

Who has been buying Kuramoto Co., Ltd. stock?: 4 distinct investors have filed 8 disclosed large-shareholding filings in Kuramoto Co., Ltd. (5216), 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 Kuramoto Co., Ltd. have?: Kuramoto Co., Ltd. has 8 buy-side and 4 sell-side disclosures on record, covering ¥2.2B ($14.0M) in total reported value, spanning 2021-09-09 to 2026-04-06.
Where does StockDrifts get Kuramoto 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 Kuramoto Co., Ltd.. For how StockDrifts scores these disclosures, see the Japan insider signal tier research, or browse every Japanese stock we track.