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

7 distinct investors have filed 18 disclosed large-shareholding filings in Cookbiz Co.,Ltd. (6558), most recently on 2026-03-05. 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 Cookbiz Co.,Ltd. have?

Cookbiz Co.,Ltd. has 18 buy-side and 31 sell-side disclosures on record, covering ¥668M ($4.3M) in total reported value, spanning 2021-04-21 to 2026-03-05.

Where does StockDrifts get Cookbiz 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.

Cookbiz Co.,Ltd. 6558

Company

クックビズ株式会社Cookbiz Co.,Ltd.

Investors

Buys

Total Value

¥668M ($4.3M)

Avg Return

-11.87%

Last Filing

2026-03-05

Cookbiz Co.,Ltd. (6558) has 18 disclosed large-shareholding filings and 31 disclosed disposals on record, filed by 7 distinct investors. Together those filings cover ¥668M ($4.3M) in reported transaction value. The earliest filing StockDrifts holds for Cookbiz Co.,Ltd. is dated 2021-04-21; the most recent is 2026-03-05. 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 -11.87%, 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
2026-08-06	BUY	Market Buy	株式会社SBI証券 SBI SECURITIES Co.,Ltd.	other	239.4K	¥687	-2.6%	¥19M ($123K)
2026-03-05	BUY	Market Buy	山本新九郎 YAMAMOTO SHINKUROU	passive	333.1K	¥720	-3.9%	¥23M ($147K)
2026-03-05	BUY	Market Buy	山本新九郎 YAMAMOTO SHINKUROU	passive	333.1K	¥720	-3.9%	¥23M ($147K)
2025-12-24	BUY	Market Buy	山本新九郎 YAMAMOTO SHINKURO	passive	308.5K	¥818	-15.4%	¥24M ($153K)
2025-12-24	BUY	Market Buy	山本新九郎 YAMAMOTO SHINKURO	passive	301.6K	¥818	-15.4%	¥30M ($195K)
2025-12-17	BUY	unknown	株式会社OICグループ OIC Group Co., Ltd.	strategic	140.0K	¥704	-1.7%	¥99M ($636K)
2025-12-17	BUY	unknown	株式会社OICグループ OIC Group Co., Ltd.	strategic	140.0K	¥704	-1.7%	¥99M ($636K)
2025-12-15	BUY	Market Buy	山本新九郎 YAMAMOTO SHINKURO	passive	279.6K	¥714	-3.1%	¥14M ($90K)
2025-12-15	BUY	Market Buy	山本新九郎 YAMAMOTO SHINKURO	passive	279.6K	¥714	-3.1%	¥14M ($90K)
2025-12-12	BUY	unknown	藪ノ郁子	strategic	210.2K	¥728	+4.9%	¥145M ($938K)
2025-12-12	SELL	unknown	藪ノ賢次	other	908.8K	¥728	+4.9%	¥629M ($4.1M)
2025-12-12	BUY	unknown	藪ノ郁子	strategic	210.2K	¥728	+4.9%	¥145M ($938K)
2025-12-12	BUY	unknown	藪ノ賢次	other	1.0M	¥728	+4.9%	¥726M ($4.7M)
2025-12-09	BUY	Market Buy	山本新九郎 YAMAMOTO SHINKURO	passive	264.7K	¥650	+6.5%	¥39M ($251K)
2025-12-09	BUY	Market Buy	山本新九郎 YAMAMOTO SHINKURO	passive	260.0K	¥650	+6.5%	¥24M ($152K)
2025-12-04	BUY	Market Buy	山本新九郎 YAMAMOTO SHINKURO	passive	223.7K	¥584	+18.5%	¥13M ($85K)
2025-12-04	BUY	Market Buy	山本新九郎 YAMAMOTO SHINKURO	passive	223.7K	¥584	+18.5%	¥13M ($85K)
2025-10-29	BUY	Market Buy	山本新九郎 YAMAMOTO SHINKURO	passive	205.0K	¥620	+11.6%	¥22M ($143K)
2025-10-29	BUY	Market Buy	山本新九郎 YAMAMOTO SHINKURO	passive	201.0K	¥620	+11.6%	¥20M ($127K)
2025-10-29	BUY	Market Buy	山本新九郎 YAMAMOTO SHINKURO	passive	169.1K	¥620	+11.6%	¥18M ($117K)
2025-10-29	BUY	Market Buy	山本新九郎 YAMAMOTO SHINKURO	passive	169.1K	¥620	+11.6%	¥18M ($117K)
2025-10-29	BUY	Market Buy	山本新九郎 YAMAMOTO SHINKURO	passive	201.0K	¥620	+11.6%	¥20M ($127K)
2025-09-16	BUY	Market Buy	山本新九郎 YAMAMOTO SHINKURO	passive	139.8K	¥659	+5.0%	¥92M ($594K)
2025-09-16	BUY	Market Buy	山本新九郎 YAMAMOTO SHINKURO	passive	187.3K	¥659	+5.0%	¥123M ($796K)
2025-01-24	SELL	unknown	藪ノ郁子 Ikuko Yabuno	strategic	210.2K	¥787	+12.1%	¥2M ($10K)
2025-01-24	SELL	unknown	藪ノ郁子 Ikuko Yabuno	strategic	210.2K	¥787	+12.1%	¥2M ($11K)
2025-01-24	SELL	unknown	藪ノ賢次 Yabuno Kenji	other	1.0M	¥787	+12.1%	¥6M ($40K)
2025-01-24	SELL	unknown	藪ノ賢次 Yabuno Kenji	other	1.0M	¥787	+12.1%	¥5M ($31K)
2024-12-19	BUY	Market Buy	株式会社SBI証券 SBI SECURITIES Co.,Ltd.	other	211.8K	¥772	-10.4%	¥17M ($107K)
2024-08-01	SELL	unknown	藪ノ郁子 Ikuko Yabuno	strategic	211.8K	¥1,162	+40.5%	¥324K ($2K)
2024-08-01	SELL	unknown	藪ノ郁子 Ikuko Yabuno	strategic	211.8K	¥1,162	+40.5%	¥324K ($2K)
2024-08-01	BUY	unknown	藪ノ賢次 Yabuno Kenji	other	1.1M	¥1,162	-40.5%	¥1.2B ($7.9M)
2024-08-01	BUY	unknown	藪ノ賢次 Yabuno Kenji	other	1.1M	¥1,162	-40.5%	¥1.2B ($7.9M)
2024-01-31	BUY	unknown	藪ノ賢次 Yabuno Kenji	other	1.1M	¥1,470	-52.9%	¥1.6B ($10.0M)
2024-01-31	SELL	unknown	藪ノ郁子 Ikuko Yabuno	strategic	212.1K	¥1,470	+52.9%	¥2M ($11K)
2024-01-31	SELL	unknown	藪ノ郁子 Ikuko Yabuno	strategic	211.8K	¥1,470	+52.9%	¥2M ($13K)
2024-01-31	SELL	unknown	藪ノ郁子 Ikuko Yabuno	strategic	212.1K	¥1,470	+52.9%	¥2M ($11K)
2024-01-31	BUY	unknown	藪ノ賢次 Yabuno Kenji	other	1.1M	¥1,470	-52.9%	¥1.6B ($10.0M)
2024-01-31	BUY	unknown	藪ノ賢次 Yabuno Kenji	other	1.1M	¥1,470	-52.9%	¥1.6B ($10.0M)
2024-01-11	SELL	unknown	藪ノ郁子 Ikuko Yabuno	strategic	213.3K	¥1,140	+39.3%	¥17M ($107K)
2024-01-11	SELL	unknown	藪ノ郁子 Ikuko Yabuno	strategic	213.3K	¥1,140	+39.3%	¥17M ($107K)
2024-01-11	SELL	unknown	藪ノ賢次 Yabuno Kenji	other	1.1M	¥1,140	+39.3%	¥51M ($326K)
2024-01-11	SELL	unknown	藪ノ賢次 Yabuno Kenji	other	1.1M	¥1,140	+39.3%	¥51M ($326K)
2023-11-07	BUY	Market Buy	株式会社SBI証券 SBI SECURITIES Co.,Ltd.	other	189.0K	¥1,013	-31.7%	¥17M ($112K)
2023-10-20	BUY	Market Buy	コモンズ投信株式会社 commons asset management inc.	passive	171.7K	¥921	-24.9%	¥29M ($188K)
2023-04-11	BUY	Market Buy	コモンズ投信株式会社 Commons Asset Management	passive	137.9K	¥1,200	-42.3%	¥165M ($1.1M)
2023-04-11	BUY	Market Buy	コモンズ投信株式会社 commons asset management inc.	passive	139.3K	¥1,200	-42.3%	¥167M ($1.1M)
2022-11-18	SELL	unknown	藪ノ郁子 Ikuko Yabuno	strategic	218.5K	¥1,281	+46.0%	¥5M ($31K)
2022-11-18	SELL	unknown	藪ノ郁子 Ikuko Yabuno	strategic	218.5K	¥1,281	+46.0%	¥5M ($31K)
2022-11-18	SELL	unknown	藪ノ賢次 Yabuno Kenji	other	1.1M	¥1,281	+46.0%	¥23M ($150K)

Showing the 50 most recent of 75 filings.

Frequently asked questions

Who has been buying Cookbiz Co.,Ltd. stock?: 7 distinct investors have filed 18 disclosed large-shareholding filings in Cookbiz Co.,Ltd. (6558), most recently on 2026-03-05. 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 Cookbiz Co.,Ltd. have?: Cookbiz Co.,Ltd. has 18 buy-side and 31 sell-side disclosures on record, covering ¥668M ($4.3M) in total reported value, spanning 2021-04-21 to 2026-03-05.
Where does StockDrifts get Cookbiz 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 Cookbiz Co.,Ltd.. For how StockDrifts scores these disclosures, see the Japan insider signal tier research, or browse every Japanese stock we track.