Who has been buying Seyfert Ltd. stock?

5 distinct investors have filed 20 disclosed large-shareholding filings in Seyfert Ltd. (9213), 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 Seyfert Ltd. have?

Seyfert Ltd. has 20 buy-side and 5 sell-side disclosures on record, covering ¥440M ($2.8M) in total reported value, spanning 2022-02-14 to 2026-04-06.

Where does StockDrifts get Seyfert 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.

Seyfert Ltd. 9213

Company

株式会社セイファートSeyfert Ltd.

Investors

Buys

Total Value

¥440M ($2.8M)

Avg Return

+0.54%

Last Filing

2026-04-06

Seyfert Ltd. (9213) has 20 disclosed large-shareholding filings and 5 disclosed disposals on record, filed by 5 distinct investors. Together those filings cover ¥440M ($2.8M) in reported transaction value. The earliest filing StockDrifts holds for Seyfert Ltd. is dated 2022-02-14; 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 +0.54%, 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
2026-04-06	BUY	unknown	株式会社アーム ARM INC	activist	256.3K	¥907	+4.7%	¥21M ($137K)
2026-04-06	BUY	Market Buy	株式会社アーム ARM INC	activist	256.3K	¥907	+4.7%	¥21M ($137K)
2026-03-19	BUY	Market Buy	株式会社アーム ARM INC	activist	232.8K	¥765	+29.7%	¥20M ($128K)
2026-03-19	BUY	unknown	株式会社アーム ARM INC	activist	232.8K	¥765	+29.7%	¥20M ($128K)
2026-03-09	BUY	Market Buy	株式会社アーム ARM INC	activist	206.8K	¥714	+38.9%	¥10M ($64K)
2026-03-09	BUY	unknown	株式会社アーム ARM INC	activist	206.8K	¥714	+38.9%	¥10M ($64K)
2026-03-04	BUY	unknown	株式会社アーム ARM INC	activist	192.8K	¥675	+47.0%	¥4M ($28K)
2026-03-04	BUY	unknown	株式会社アーム ARM INC	activist	192.8K	¥675	+47.0%	¥4M ($28K)
2026-03-04	BUY	Market Buy	株式会社アーム ARM INC	activist	192.8K	¥675	+47.0%	¥4M ($28K)
2025-12-10	SELL	unknown	マネックス証券株式会社 Monex, Inc.	other	20.8K	¥754	-31.6%	¥36M ($229K)
2025-10-14	SELL	unknown	マネックス証券株式会社 Monex, Inc.	other	68.0K	¥908	-9.3%	¥23M ($151K)
2025-10-03	BUY	Market Buy	マネックス証券株式会社 Monex, Inc.	other	93.8K	¥1,109	-10.6%	¥26M ($169K)
2025-09-24	SELL	unknown	マネックス証券株式会社 Monex, Inc.	other	70.1K	¥1,515	+34.5%	¥29M ($188K)
2025-09-22	SELL	unknown	マネックス証券株式会社 Monex, Inc.	other	89.4K	¥1,251	+20.7%	¥108M ($694K)
2025-09-17	BUY	unknown	マネックス証券株式会社 Monex, Inc.	other	175.4K	¥1,027	-3.4%	¥180M ($1.2M)
2024-11-22	BUY	Market Buy	株式会社ビューティガレージ BEAUTY GARAGE INC.	activist	115.7K	¥924	+7.4%	¥15M ($98K)
2024-10-07	BUY	Market Buy	株式会社ビューティガレージ BEAUTY GARAGE INC.	activist	99.3K	¥998	-0.6%	¥15M ($99K)
2024-06-06	BUY	Market Buy	株式会社ビューティガレージ BEAUTY GARAGE INC.	activist	84.0K	¥1,072	-7.5%	¥90M ($581K)
2024-02-27	BUY	Market Buy	株式会社ビューティガレージ BEAUTY GARAGE Inc.	activist	67.3K	¥1,144	-13.3%	¥77M ($497K)
2023-12-22	BUY	Market Buy	株式会社アーム ARM INC	activist	186.3K	¥1,083	-8.4%	¥17M ($111K)
2023-12-22	BUY	Market Buy	株式会社アーム ARM INC	activist	186.3K	¥1,083	-8.4%	¥17M ($111K)
2023-12-22	BUY	Market Buy	株式会社アーム ARM INC	activist	186.3K	¥1,083	-8.4%	¥17M ($111K)
2023-10-19	BUY	Market Buy	株式会社アーム ARM INC	activist	170.5K	¥1,066	-6.9%	¥19M ($120K)
2023-10-19	BUY	Market Buy	株式会社アーム ARM INC	activist	170.5K	¥1,066	-6.9%	¥19M ($120K)
2023-10-19	BUY	Market Buy	株式会社アーム ARM INC	activist	170.5K	¥1,066	-6.9%	¥19M ($120K)
2023-10-19	BUY	Market Buy	株式会社アーム ARM INC	activist	170.5K	¥1,066	-6.9%	¥19M ($120K)
2023-10-18	BUY	Market Buy	株式会社アーム ARM INC	activist	170.5K	¥1,051	-5.6%	¥18M ($118K)
2023-10-18	BUY	Market Buy	株式会社アーム ARM INC	activist	170.5K	¥1,051	-5.6%	¥18M ($118K)
2023-10-18	BUY	Market Buy	株式会社アーム ARM INC	activist	158.9K	¥1,051	-5.6%	¥6M ($39K)
2023-10-18	BUY	Market Buy	株式会社アーム ARM INC	activist	158.9K	¥1,051	-5.6%	¥6M ($39K)
2023-09-08	SELL	Market Buy	株式会社IBJ IBJ,Inc.	passive	0	¥1,180	+15.9%	¥151M ($972K)
2023-08-03	BUY	Market Buy	株式会社アーム ARM INC	passive	153.1K	¥1,005	-1.3%	¥45M ($289K)
2023-08-03	BUY	Market Buy	株式会社アーム ARM INC	passive	153.1K	¥1,005	-1.3%	¥45M ($289K)
2023-08-03	BUY	Market Buy	株式会社アーム ARM INC	passive	153.1K	¥1,005	-1.3%	¥45M ($289K)
2023-05-16	BUY	Market Buy	株式会社アーム ARM INC	passive	108.5K	¥1,007	-1.5%	¥18M ($115K)
2023-05-16	BUY	Market Buy	株式会社アーム ARM INC	passive	108.5K	¥1,007	-1.5%	¥18M ($115K)
2023-04-10	BUY	Market Buy	株式会社アーム Arm inc	passive	90.7K	¥1,150	-13.7%	¥104M ($673K)
2023-04-10	BUY	Market Buy	株式会社アーム Arm inc	passive	90.7K	¥1,150	-13.7%	¥104M ($673K)
2022-11-22	BUY	Market Buy	株式会社IBJ IBJ,Inc.	passive	127.7K	¥1,167	-15.0%	¥18M ($117K)
2022-09-30	BUY	Market Buy	株式会社IBJ IBJ,Inc.	passive	112.2K	¥1,023	-3.0%	¥24M ($153K)
2022-09-30	BUY	Market Buy	株式会社IBJ IBJ,Inc.	passive	112.2K	¥1,023	-3.0%	¥24M ($153K)
2022-08-22	BUY	Market Buy	株式会社IBJ IBJ,Inc.	passive	66.5K	¥1,093	-9.2%	¥73M ($469K)
2022-08-22	BUY	Market Buy	株式会社IBJ IBJ,Inc.	passive	89.0K	¥1,093	-9.2%	¥25M ($159K)
2022-08-22	BUY	Market Buy	株式会社IBJ IBJ,Inc.	passive	89.0K	¥1,093	-9.2%	¥25M ($159K)
2022-08-22	BUY	Market Buy	株式会社IBJ IBJ,Inc.	passive	66.5K	¥1,093	-9.2%	¥73M ($469K)
2022-02-14	BUY	unknown	株式会社ビューティープロスペリティ― BeautyProsperity Ltd.	strategic	308.0K	¥1,167	-15.0%	¥359M ($2.3M)

Frequently asked questions

Who has been buying Seyfert Ltd. stock?: 5 distinct investors have filed 20 disclosed large-shareholding filings in Seyfert Ltd. (9213), 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 Seyfert Ltd. have?: Seyfert Ltd. has 20 buy-side and 5 sell-side disclosures on record, covering ¥440M ($2.8M) in total reported value, spanning 2022-02-14 to 2026-04-06.
Where does StockDrifts get Seyfert 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 Seyfert Ltd.. For how StockDrifts scores these disclosures, see the Japan insider signal tier research, or browse every Japanese stock we track.