Who has been buying Kaizen Platform, Inc. stock?

14 distinct investors have filed 31 disclosed large-shareholding filings in Kaizen Platform, Inc. (4170), most recently on 2026-05-12. 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 Kaizen Platform, Inc. have?

Kaizen Platform, Inc. has 31 buy-side and 23 sell-side disclosures on record, covering ¥5.5B ($35.6M) in total reported value, spanning 2021-04-07 to 2026-05-12.

Where does StockDrifts get Kaizen Platform, Inc. 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.

Kaizen Platform, Inc. 4170

Company

株式会社Ｋａｉｚｅｎ　ＰｌａｔｆｏｒｍKaizen Platform, Inc.

Investors

Buys

Total Value

¥5.5B ($35.6M)

Avg Return

-44.95%

Last Filing

2026-05-12

Kaizen Platform, Inc. (4170) has 31 disclosed large-shareholding filings and 23 disclosed disposals on record, filed by 14 distinct investors. Together those filings cover ¥5.5B ($35.6M) in reported transaction value. The earliest filing StockDrifts holds for Kaizen Platform, Inc. is dated 2021-04-07; the most recent is 2026-05-12. 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 -44.95%, 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
2026-07-23	SELL	unknown	楽天証券株式会社 Rakuten Securities Inc	other	509.8K	¥118	+0.8%	¥49M ($314K)
2026-07-07	SELL	unknown	株式会社SBI証券 SBI SECURITIES Co.,Ltd.	other	1.9M	¥112	-3.6%	¥56M ($362K)
2026-07-02	BUY	Market Buy	株式会社SBI証券 SBI SECURITIES Co.,Ltd.	other	2.4M	¥110	+6.4%	¥59M ($382K)
2026-06-25	BUY	Market Buy	株式会社SBI証券 SBI SECURITIES Co.,Ltd.	other	1.9M	¥102	+16.7%	¥3M ($22K)
2026-06-23	BUY	Market Buy	黒田直樹 Naoki Kuroda	passive	1.6M	¥101	+22.8%	¥19M ($121K)
2026-06-19	SELL	unknown	株式会社SBI証券 SBI SECURITIES Co.,Ltd.	other	1.8M	¥100	-24.0%	¥171K ($1K)
2026-06-18	BUY	Market Buy	株式会社SBI証券 SBI SECURITIES Co.,Ltd.	other	1.8M	¥104	+19.2%	¥25M ($162K)
2026-06-03	BUY	Market Buy	黒田直樹 Naoki Kuroda	passive	1.4M	¥135	-17.8%	¥25M ($159K)
2026-05-12	BUY	Market Buy	株式会社SBI証券 SBI SECURITIES Co.,Ltd.	other	1.6M	¥165	-21.8%	¥13M ($83K)
2026-04-21	BUY	Market Buy	株式会社SBI証券 SBI SECURITIES Co.,Ltd.	other	1.5M	¥175	-7.4%	¥21M ($136K)
2026-03-23	BUY	Market Buy	楽天証券株式会社 Rakuten Securities Inc	other	916.4K	¥155	+12.9%	¥5M ($31K)
2026-02-25	BUY	Market Buy	黒田直樹 Naoki Kuroda	passive	1.3M	¥170	+2.9%	¥37M ($239K)
2026-02-25	BUY	Market Buy	黒田直樹 Naoki Kuroda	passive	1.3M	¥170	+2.9%	¥37M ($239K)
2026-02-16	BUY	Market Buy	黒田直樹 Naoki Kuroda	passive	1.2M	¥170	+2.9%	¥27M ($175K)
2026-02-16	BUY	Market Buy	黒田直樹 Naoki Kuroda	passive	1.2M	¥170	+2.9%	¥27M ($175K)
2026-02-06	SELL	unknown	楽天証券株式会社 Rakuten Securities Inc	other	887.4K	¥195	+10.3%	¥34M ($221K)
2026-01-13	SELL	unknown	株式会社SBI証券 SBI SECURITIES Co.,Ltd.	other	1.4M	¥182	+3.9%	¥89M ($571K)
2026-01-07	BUY	Market Buy	株式会社SBI証券 SBI SECURITIES Co.,Ltd.	other	1.9M	¥176	-0.6%	¥125M ($804K)
2025-12-03	BUY	Market Buy	黒田直樹 Naoki Kuroda	passive	1.0M	¥182	-3.9%	¥33M ($216K)
2025-12-03	BUY	Market Buy	黒田直樹 Naoki Kuroda	passive	1.0M	¥182	-3.9%	¥33M ($216K)
2025-08-22	BUY	Market Buy	株式会社SBI証券 SBI SECURITIES Co.,Ltd.	other	1.2M	¥230	-23.9%	¥46M ($295K)
2025-08-12	BUY	Market Buy	黒田直樹 Naoki Kuroda	passive	850.7K	¥211	-17.1%	¥179M ($1.2M)
2025-08-12	BUY	Market Buy	黒田直樹 Naoki Kuroda	passive	850.7K	¥211	-17.1%	¥179M ($1.2M)
2025-07-22	SELL	unknown	株式会社SBI証券 SBI SECURITIES Co.,Ltd.	other	951.8K	¥209	+16.3%	¥80M ($516K)
2025-07-04	BUY	unknown	株式会社SBI証券 SBI SECURITIES Co.,Ltd.	other	1.3M	¥189	-7.4%	¥252M ($1.6M)
2025-01-21	SELL	unknown	株式会社SBI証券 SBI SECURITIES Co.,Ltd.	other	771.0K	¥171	-2.3%	¥50M ($324K)
2025-01-09	BUY	unknown	株式会社SBI証券 SBI SECURITIES Co.,Ltd.	other	1.1M	¥172	+1.7%	¥183M ($1.2M)
2024-12-18	BUY	Market Buy	楽天証券株式会社 Rakuten Securities Inc	other	1.1M	¥167	+4.8%	¥29M ($188K)
2024-08-21	BUY	unknown	楽天証券株式会社 Rakuten Securities Inc	other	882.4K	¥206	-15.1%	¥182M ($1.2M)
2024-07-16	SELL	negotiated	株式会社エヌ・ティ・ティ・アド NTT ADVERTISING,INC.	strategic	711.7K	¥240	+27.1%	¥86M ($554K)
2024-07-16	BUY	negotiated	株式会社エヌ・ティ・ティ・アド NTT ADVERTISING,INC.	strategic	711.7K	¥240	-27.1%	¥86M ($554K)
2023-07-19	SELL	Market Buy	クープランド・カーディフ・アセット・マネジメント・エルエルピー(Coupland Cardiff Asset Management LLP) Coupland Cardiff Asset Management LLP	passive	815.0K	¥346	+49.4%	¥71M ($458K)
2023-06-22	SELL	Market Buy	クープランド・カーディフ・アセット・マネジメント・エルエルピー(Coupland Cardiff Asset Management LLP) Coupland Cardiff Asset Management LLP	passive	1.0M	¥333	+47.5%	¥74M ($477K)
2023-06-15	SELL	Market Buy	クープランド・カーディフ・アセット・マネジメント・エルエルピー(Coupland Cardiff Asset Management LLP) Coupland Cardiff Asset Management LLP	passive	1.2M	¥326	+46.3%	¥59M ($379K)
2023-06-08	SELL	Market Buy	クープランド・カーディフ・アセット・マネジメント・エルエルピー(Coupland Cardiff Asset Management LLP) Coupland Cardiff Asset Management LLP	passive	1.4M	¥337	+48.1%	¥74M ($476K)
2023-04-17	SELL	Market Buy	クープランド・カーディフ・アセット・マネジメント・エルエルピー(Coupland Cardiff Asset Management LLP) Coupland Cardiff Asset Management LLP	passive	1.6M	¥381	+54.1%	¥64M ($413K)
2022-07-25	SELL	unknown	みずほ証券株式会社 Mizuho Securities Co., Ltd.	other	33.7K	¥409	+57.2%	¥682K ($4K)
2022-07-25	BUY	unknown	アセットマネジメントOne株式会社 Asset Management One Co., Ltd.	other	781.8K	¥409	-57.2%	¥316M ($2.0M)
2022-07-07	SELL	unknown	みずほ証券株式会社 Mizuho Securities Co., Ltd.	other	34.8K	¥407	+57.0%	¥3M ($22K)
2022-07-07	BUY	unknown	アセットマネジメントOne株式会社 Asset Management One Co., Ltd.	other	972.3K	¥407	-57.0%	¥391M ($2.5M)
2022-04-22	SELL	Market Buy	みずほ証券株式会社 Mizuho Securities Co., Ltd.	other	43.5K	¥500	+65.0%	¥5M ($32K)
2022-04-22	BUY	Market Buy	アセットマネジメントOne株式会社 Asset Management One Co., Ltd.	other	1.2M	¥500	-65.0%	¥90M ($578K)
2022-03-28	SELL	unknown	石橋利真 Ishibashi Toshimasa	strategic	782.5K	¥390	+55.1%	¥69M ($447K)
2022-03-08	SELL	unknown	石橋利真 Ishibashi Toshimasa	strategic	959.7K	¥337	+48.1%	¥60M ($390K)
2022-03-08	BUY	unknown	石橋利真 Ishibashi Toshimasa	strategic	959.7K	¥337	-48.1%	¥60M ($390K)
2022-03-03	BUY	Market Buy	ジェー・ピー・モルガン・セキュリティーズ・ピーエルシー J.P. Morgan Securities plc	other	80.9K	¥369	-52.6%	¥8M ($51K)
2022-03-03	SELL	Market Buy	JPモルガン証券株式会社 JPMorgan Securities Japan Co., Ltd.	other	61.8K	¥369	+52.6%	¥19M ($125K)
2022-03-03	BUY	Market Buy	JPモルガン・アセット・マネジメント株式会社 JPMorgan Asset Management (Japan) Limited	passive	612.0K	¥369	-52.6%	¥221M ($1.4M)
2022-02-22	BUY	unknown	株式会社ハック思考 Hack Thinking Co., Ltd.	strategic	900.0K	¥337	-48.1%	¥303M ($2.0M)
2022-02-22	BUY	unknown	須藤憲司 Sudo Kenji	strategic	3.1M	¥337	-48.1%	¥1.0B ($6.6M)

Showing the 50 most recent of 74 filings.

Frequently asked questions

Who has been buying Kaizen Platform, Inc. stock?: 14 distinct investors have filed 31 disclosed large-shareholding filings in Kaizen Platform, Inc. (4170), most recently on 2026-05-12. 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 Kaizen Platform, Inc. have?: Kaizen Platform, Inc. has 31 buy-side and 23 sell-side disclosures on record, covering ¥5.5B ($35.6M) in total reported value, spanning 2021-04-07 to 2026-05-12.
Where does StockDrifts get Kaizen Platform, Inc. 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 Kaizen Platform, Inc.. For how StockDrifts scores these disclosures, see the Japan insider signal tier research, or browse every Japanese stock we track.