Who has been buying Kaken Pharmaceutical Co., Ltd. stock?

4 distinct investors have filed 8 disclosed large-shareholding filings in Kaken Pharmaceutical Co., Ltd. (4521), most recently on 2024-11-26. 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 Kaken Pharmaceutical Co., Ltd. have?

Kaken Pharmaceutical Co., Ltd. has 8 buy-side and 4 sell-side disclosures on record, covering ¥24.7B ($159.3M) in total reported value, spanning 2021-04-23 to 2024-11-26.

Where does StockDrifts get Kaken Pharmaceutical 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.

Kaken Pharmaceutical Co., Ltd. 4521

Company

科研製薬株式会社Kaken Pharmaceutical Co., Ltd.

Investors

Buys

Total Value

¥24.7B ($159.3M)

Avg Return

-1.78%

Last Filing

2024-11-26

Kaken Pharmaceutical Co., Ltd. (4521) has 8 disclosed large-shareholding filings and 4 disclosed disposals on record, filed by 4 distinct investors. Together those filings cover ¥24.7B ($159.3M) in reported transaction value. The earliest filing StockDrifts holds for Kaken Pharmaceutical Co., Ltd. is dated 2021-04-23; the most recent is 2024-11-26. 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 -1.78%, 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
2026-08-07	SELL	unknown	アセットマネジメントOne株式会社	other	569.8K	¥3,900	-3.0%	¥2.1B ($13.4M)
2026-08-07	BUY	unknown	みずほ信託銀行株式会社	other	199.7K	¥3,900	+3.0%	¥779M ($5.0M)
2026-08-07	BUY	Market Buy	株式会社みずほ銀行	strategic	1.5M	¥3,900	+3.0%	¥224M ($1.4M)
2024-11-26	SELL	unknown	株式会社南青山不動産 Minami Aoyama Real Estate Co., Ltd.	activist	372.4K	¥4,330	+4.4%	¥537M ($3.5M)
2024-11-26	BUY	unknown	野村絢 Aya Nomura (Murakami family)	activist	1.9M	¥4,330	-4.4%	¥8.0B ($51.6M)
2024-11-26	BUY	unknown	株式会社シティインデックスイレブンス City Index Eleven Co., Ltd.	activist	30.0K	¥4,330	-4.4%	¥13.9B ($89.8M)
2024-06-26	BUY	unknown	株式会社南青山不動産 Minami Aoyama Real Estate Co., Ltd.	activist	497.6K	¥3,824	+8.3%	¥1.9B ($12.3M)
2024-06-26	BUY	unknown	野村絢 Aya Nomura (Murakami family)	activist	2.3M	¥3,824	+8.3%	¥8.8B ($57.0M)
2024-06-26	BUY	unknown	株式会社シティインデックスイレブンス City Index Eleven Co., Ltd.	activist	100	¥3,824	+8.3%	¥382K ($2K)
2024-06-05	BUY	unknown	野村絢 Aya Nomura (Murakami family)	activist	2.3M	¥3,855	+7.4%	¥8.9B ($57.5M)
2024-06-05	BUY	unknown	株式会社シティインデックスイレブンス City Index Eleven Co., Ltd.	activist	100	¥3,855	+7.4%	¥386K ($2K)
2024-03-27	SELL	subscription	シルチェスター・インターナショナル・インベスターズ・エルエルピー (Silchester International Investors LLP) Silchester International Investors LLP	activist	2.2M	¥3,586	-15.4%	¥1.8B ($11.5M)
2023-10-12	SELL	subscription	シルチェスター・インターナショナル・インベスターズ・エルエルピー (Silchester International Investors LLP) Silchester International Investors LLP	activist	2.7M	¥3,466	-19.4%	¥1.7B ($10.8M)
2023-09-19	SELL	subscription	シルチェスター・インターナショナル・インベスターズ・エルエルピー (Silchester International Investors LLP) Silchester International Investors LLP	activist	3.2M	¥3,616	-14.5%	¥1.8B ($11.6M)
2022-03-28	BUY	subscription	シルチェスター・インターナショナル・インベスターズ・エルエルピー (Silchester International Investors LLP) Silchester International Investors LLP	activist	3.7M	¥4,055	+2.1%	¥1.9B ($12.0M)
2021-10-28	BUY	subscription	シルチェスター・インターナショナル・インベスターズ・エルエルピー (Silchester International Investors LLP) Silchester International Investors LLP	activist	3.2M	¥4,500	-8.0%	¥2.1B ($13.3M)
2021-05-25	BUY	subscription	シルチェスター・インターナショナル・インベスターズ・エルエルピー (Silchester International Investors LLP) Silchester International Investors LLP	activist	2.8M	¥4,455	-7.1%	¥2.1B ($13.5M)
2021-04-23	BUY	subscription	シルチェスター・インターナショナル・インベスターズ・エルエルピー (Silchester International Investors LLP) Silchester International Investors LLP	activist	2.3M	¥4,465	-7.3%	¥10.3B ($66.2M)

Frequently asked questions

Who has been buying Kaken Pharmaceutical Co., Ltd. stock?: 4 distinct investors have filed 8 disclosed large-shareholding filings in Kaken Pharmaceutical Co., Ltd. (4521), most recently on 2024-11-26. 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 Kaken Pharmaceutical Co., Ltd. have?: Kaken Pharmaceutical Co., Ltd. has 8 buy-side and 4 sell-side disclosures on record, covering ¥24.7B ($159.3M) in total reported value, spanning 2021-04-23 to 2024-11-26.
Where does StockDrifts get Kaken Pharmaceutical 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 Kaken Pharmaceutical Co., Ltd.. For how StockDrifts scores these disclosures, see the Japan insider signal tier research, or browse every Japanese stock we track.