Who has been buying MK Seiko Co., Ltd. stock?

6 distinct investors have filed 4 disclosed large-shareholding filings in MK Seiko Co., Ltd. (5906), most recently on 2025-05-26. 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 MK Seiko Co., Ltd. have?

MK Seiko Co., Ltd. has 4 buy-side and 4 sell-side disclosures on record, covering ¥293M ($1.9M) in total reported value, spanning 2021-05-18 to 2025-05-26.

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.

MK Seiko Co., Ltd. 5906

Company

エムケー精工株式会社MK Seiko Co., Ltd.

Investors

Buys

Total Value

¥293M ($1.9M)

Avg Return

+127.97%

Last Filing

2025-05-26

MK Seiko Co., Ltd. (5906) has 4 disclosed large-shareholding filings and 4 disclosed disposals on record, filed by 6 distinct investors. Together those filings cover ¥293M ($1.9M) in reported transaction value. The earliest filing StockDrifts holds for MK Seiko Co., Ltd. is dated 2021-05-18; the most recent is 2025-05-26. Across these filings the average return since disclosure is +127.97%, 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
2025-05-26	SELL	negotiated	株式会社八十二銀行 The Hachijuni Bank, Ltd.	strategic	688.0K	¥469	-64.6%	¥15M ($99K)
2025-05-26	SELL	negotiated	株式会社長野銀行 Nagano Bank, Ltd.	strategic	0	¥469	-64.6%	¥99M ($637K)
2025-05-26	BUY	negotiated	八十二リース株式会社 Eighty Two Lease Co., Ltd.	strategic	5.8K	¥469	-	-
2025-04-04	BUY	unknown	丸山はる代 Haruyo Maruyama	strategic	825.8K	¥433	+78.3%	¥291M ($1.9M)
2025-04-04	SELL	unknown	丸山永樹(相続人代表丸山はる代) Eiki Maruyama (Heir Representative Haruyo Maruyama)	unknown	0	¥433	-78.3%	¥588M ($3.8M)
2023-06-08	BUY	negotiated	株式会社八十二銀行 The Hachijuni Bank, Ltd.	strategic	721.0K	¥378	+104.2%	¥273M ($1.8M)
2023-06-08	BUY	negotiated	八十二リース株式会社 Eighty Two Lease Co., Ltd.	strategic	5.8K	¥378	+104.2%	¥2M ($14K)
2023-06-08	BUY	negotiated	株式会社長野銀行 Nagano Bank, Ltd.	strategic	210.0K	¥378	+104.2%	¥79M ($512K)
2021-05-18	SELL	Market Buy	東京中小企業投資育成株式会社 TOKYO SMALL AND MEDIUM BUSINESS INVESTMENT & CONSULTATION CO.,LTD	passive	1.2M	¥422	-82.9%	¥47M ($301K)

Frequently asked questions

Who has been buying MK Seiko Co., Ltd. stock?: 6 distinct investors have filed 4 disclosed large-shareholding filings in MK Seiko Co., Ltd. (5906), most recently on 2025-05-26. 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 MK Seiko Co., Ltd. have?: MK Seiko Co., Ltd. has 4 buy-side and 4 sell-side disclosures on record, covering ¥293M ($1.9M) in total reported value, spanning 2021-05-18 to 2025-05-26.
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.

More on this data

Every trade listed above comes from an official regulatory disclosure. For how StockDrifts scores these disclosures, see the Japan insider signal tier research, or browse every Japanese stock we track.