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

7 distinct investors have filed 7 disclosed large-shareholding filings in TSUKUBASEIKO Co.,Ltd. (6596), most recently on 2025-11-07. 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 TSUKUBASEIKO Co.,Ltd. have?

TSUKUBASEIKO Co.,Ltd. has 7 buy-side and 3 sell-side disclosures on record, covering ¥2.2B ($14.2M) in total reported value, spanning 2021-07-14 to 2025-11-07.

Where does StockDrifts get TSUKUBASEIKO 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.

TSUKUBASEIKO Co.,Ltd. 6596

Company

筑波精工株式会社TSUKUBASEIKO Co.,Ltd.

Investors

Buys

Total Value

¥2.2B ($14.2M)

Avg Return

-15.14%

Last Filing

2025-11-07

TSUKUBASEIKO Co.,Ltd. (6596) has 7 disclosed large-shareholding filings and 3 disclosed disposals on record, filed by 7 distinct investors. Together those filings cover ¥2.2B ($14.2M) in reported transaction value. The earliest filing StockDrifts holds for TSUKUBASEIKO Co.,Ltd. is dated 2021-07-14; the most recent is 2025-11-07. 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 -15.14%, 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
2025-11-07	BUY	Market Buy	アストロンキャピタル株式会社代表取締役陳英世 Chin Honei	passive	275.0K	¥1,000	-1.0%	¥275M ($1.8M)
2025-10-31	SELL	Market Buy	合同会社TCTS05 GKTCTS05	passive	0	¥1,000	+1.0%	¥275M ($1.8M)
2025-10-17	BUY	Market Buy	合同会社TCTS05 GKTCTS05	passive	275.0K	¥1,000	-1.0%	¥275M ($1.8M)
2024-11-06	BUY	Market Buy	合同会社TCTS05 GKTCTS05	passive	275.0K	¥1,000	-1.0%	¥275M ($1.8M)
2024-08-19	BUY	unknown	VTONE株式会社代表取締役余東 VTONE Co.,Ltd.	other	443.7K	¥1,000	-1.0%	¥444M ($2.9M)
2024-08-19	BUY	unknown	VTONE株式会社代表取締役余東 VTONE Co.,Ltd.	other	443.7K	¥1,000	-1.0%	¥67M ($430K)
2024-06-12	SELL	Market Buy	株式会社TNPオンザロード TNP On The Road Corporation	passive	3.9K	¥1,000	+1.0%	¥4K ($25)
2024-06-10	BUY	unknown	VTONE株式会社 VTONE Co.,Ltd.	other	377.1K	¥1,000	-1.0%	¥377M ($2.4M)
2024-06-10	BUY	unknown	VTONE株式会社代表取締役余東 VTONE Co.,Ltd.	other	377.1K	¥1,000	-1.0%	¥377M ($2.4M)
2024-06-10	BUY	unknown	VTONE株式会社代表取締役余東 VTONE Co.,Ltd.	other	443.7K	¥1,000	-1.0%	¥444M ($2.9M)
2024-06-10	BUY	unknown	VTONE株式会社代表取締役余東 VTONE Co.,Ltd.	other	443.7K	¥1,000	-1.0%	¥444M ($2.9M)
2024-02-22	BUY	Market Buy	株式会社TNPオンザロード TNP On The Road Corporation	passive	381.0K	¥1,250	-20.8%	¥476M ($3.1M)
2024-02-22	BUY	Market Buy	株式会社TNPオンザロード TNP On The Road Corporation	passive	381.0K	¥1,250	-20.8%	¥476M ($3.1M)
2021-09-22	BUY	unknown	傅寶莱(POH FOW LAI) POH FOW LAI	other	747.0K	¥1,250	-20.8%	¥934M ($6.0M)
2021-09-22	BUY	unknown	傅寶莱(POH FOW LAI) POH FOW LAI	other	747.0K	¥1,250	-20.8%	¥934M ($6.0M)
2021-07-14	SELL	Market Buy	ゴールデン・アジア・ファンド・ベンチャーズ・リミテッド Golden Asia Fund Ventures Limited	passive	0	¥1,250	+20.8%	¥94M ($605K)
2021-07-14	BUY	Market Buy	ゴールデン・アジア・ファンド・ベンチャーズ・リミテッド Golden Asia Fund Ventures Limited	passive	0	¥1,250	-20.8%	¥94M ($605K)
2021-07-14	BUY	Market Buy	創新工業技術移轉股分有限公司(そうしんこうぎょうぎじゅついてんこふんゆうげんこうし) Innovation Industrial Technology Transfer Co., Ltd.	passive	392.9K	¥1,250	-20.8%	¥39M ($255K)
2021-07-14	BUY	Market Buy	創新工業技術移轉股分有限公司(そうしんこうぎょうぎじゅついてんこふんゆうげんこうし) Innovation Industrial Technology Transfer Co., Ltd.	passive	392.9K	¥1,250	-20.8%	¥39M ($255K)

Frequently asked questions

Who has been buying TSUKUBASEIKO Co.,Ltd. stock?: 7 distinct investors have filed 7 disclosed large-shareholding filings in TSUKUBASEIKO Co.,Ltd. (6596), most recently on 2025-11-07. 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 TSUKUBASEIKO Co.,Ltd. have?: TSUKUBASEIKO Co.,Ltd. has 7 buy-side and 3 sell-side disclosures on record, covering ¥2.2B ($14.2M) in total reported value, spanning 2021-07-14 to 2025-11-07.
Where does StockDrifts get TSUKUBASEIKO 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 TSUKUBASEIKO Co.,Ltd.. For how StockDrifts scores these disclosures, see the Japan insider signal tier research, or browse every Japanese stock we track.