Who has been buying Sompo Holdings, Inc. stock?

26 distinct investors have filed 35 disclosed large-shareholding filings in Sompo Holdings, Inc. (8630), most recently on 2025-09-19. 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 Sompo Holdings, Inc. have?

Sompo Holdings, Inc. has 35 buy-side and 19 sell-side disclosures on record, covering ¥50.3B ($324.6M) in total reported value, spanning 2021-04-01 to 2025-09-19.

Where does StockDrifts get Sompo Holdings, 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.

Sompo Holdings, Inc. 8630

Company

SOMPOホールディングス株式会社Sompo Holdings, Inc.

Investors

Buys

Total Value

¥50.3B ($324.6M)

Avg Return

+212.99%

Last Filing

2025-09-19

Sompo Holdings, Inc. (8630) has 35 disclosed large-shareholding filings and 19 disclosed disposals on record, filed by 26 distinct investors. Together those filings cover ¥50.3B ($324.6M) in reported transaction value. The earliest filing StockDrifts holds for Sompo Holdings, Inc. is dated 2021-04-01; the most recent is 2025-09-19. 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 +212.99%, 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
2025-09-19	SELL	unknown	アモーヴァ・アセットマネジメント株式会社 Amova Asset Management Co., Ltd.	other	16.8M	¥4,686	-25.4%	¥1.8B ($11.3M)
2025-09-19	SELL	unknown	三井住友トラスト・アセットマネジメント株式会社 Sumitomo Mitsui Trust Asset Management Co.,Ltd.	other	27.4M	¥4,686	-25.4%	¥29.3B ($189.2M)
2024-03-19	SELL	Market Buy	ノルウェー銀行(Norges Bank) Norges Bank	passive	16.5M	¥3,119.33	-88.4%	¥618M ($4.0M)
2023-12-20	BUY	Market Buy	ブラックロック・アセット・マネジメント・アイルランド・リミテッド BlackRock Asset Management Ireland Limited	passive	2.9M	¥2,277	+158.1%	¥1.1B ($6.8M)
2023-12-20	SELL	Market Buy	ブラックロック・インベストメント・マネジメント(ユーケー)リミテッドLimited) BlackRock Investment Management (UK	passive	378.3K	¥2,277	-158.1%	¥601M ($3.9M)
2023-12-20	BUY	Market Buy	ブラックロック・インスティテューショナル・トラスト・カンパニー、エヌ.エイ.(BlackRock Institutional Trust Company BlackRock Institutional Trust Company, N.A.	passive	4.4M	¥2,277	+158.1%	¥752M ($4.9M)
2023-12-20	BUY	Market Buy	ブラックロック・ファンド・アドバイザーズ BlackRock Fund Advisors	passive	6.1M	¥2,277	+158.1%	¥2.2B ($14.1M)
2023-12-20	BUY	Market Buy	ブラックロック・アセット・マネジメント・カナダ・リミテッド BlackRock Asset Management Canada Limited	passive	475.3K	¥2,277	+158.1%	¥1.1B ($7.0M)
2023-12-20	BUY	Market Buy	ブラックロック・ファンド・マネジャーズ・リミテッド BlackRock Fund Managers Limited	passive	1.3M	¥2,277	+158.1%	¥977M ($6.3M)
2023-12-20	BUY	Market Buy	ブラックロック(ネザーランド)BVBV) BlackRock (Netherlands	passive	1.1M	¥2,277	+158.1%	¥150M ($970K)
2023-12-20	BUY	Market Buy	ブラックロック・インベストメント・マネジメント・エルエルシー BlackRock Investment Management LLC	passive	362.4K	¥2,277	+158.1%	¥825M ($5.3M)
2023-12-20	BUY	Market Buy	ブラックロック・アドバイザーズ・エルエルシー(BlackRock Advisers BlackRock Advisers, LLC	passive	338.2K	¥2,277	+158.1%	¥770M ($5.0M)
2023-12-20	BUY	Market Buy	ブラックロック・ジャパン株式会社 BlackRock Japan Co., Ltd.	passive	6.9M	¥2,277	+158.1%	¥1.6B ($10.2M)
2023-11-07	BUY	block_purchase	ノルウェー銀行(Norges Bank) Norges Bank	passive	17.6M	¥2,175.66	+170.1%	¥151M ($976K)
2023-10-11	SELL	Market Buy	ノルウェー銀行(Norges Bank) Norges Bank	passive	17.5M	¥2,134	-175.3%	¥668M ($4.3M)
2023-09-22	SELL	Market Buy	ノルウェー銀行(Norges Bank) Norges Bank	passive	17.8M	¥2,279.33	-157.8%	¥159M ($1.0M)
2023-09-22	BUY	Market Buy	ノルウェー銀行(Norges Bank) Norges Bank	passive	17.8M	¥2,279.33	+157.8%	¥159M ($1.0M)
2023-09-07	BUY	unknown	野村アセットマネジメント株式会社 Nomura Asset Management Co., Ltd.	other	19.7M	¥2,187.33	+168.6%	¥5.0B ($32.4M)
2023-09-07	BUY	unknown	ノムラインターナショナルピーエルシー NOMURA INTERNATIONAL PLC	other	1.9M	¥2,187.33	+168.6%	¥4.2B ($27.0M)
2023-09-07	BUY	unknown	野村證券株式会社 Nomura Securities Co.,Ltd.	other	127.0K	¥2,187.33	+168.6%	¥29.3B ($188.9M)
2023-09-07	SELL	Market Buy	ノルウェー銀行(Norges Bank) Norges Bank	passive	17.9M	¥2,187.33	-168.6%	¥532M ($3.4M)
2023-05-01	SELL	Market Buy	三菱UFJモルガン・スタンレー証券株式会社 Mitsubishi UFJ Morgan Stanley Securities Co., Ltd.	other	233.8K	¥1,905.66	-208.3%	¥1.5B ($9.4M)
2023-05-01	BUY	Market Buy	三菱UFJ国際投信株式会社 Mitsubishi UFJ Financial Group Inc.	passive	3.2M	¥1,905.66	+208.3%	¥66M ($427K)
2023-05-01	SELL	Market Buy	MUFGセキュリティーズEMEA MUFG Securities EMEA plc	other	720.0K	¥1,905.66	-208.3%	¥2.5B ($15.8M)
2023-05-01	SELL	Market Buy	三菱UFJ信託銀行株式会社 Mitsubishi UFJ Financial Group Inc.	passive	10.9M	¥1,905.66	-208.3%	¥3.6B ($23.1M)
2023-04-20	BUY	unknown	日興アセットマネジメント株式会社 Nikko Asset Management Co.,Ltd.	other	6.4M	¥1,870.66	+214.1%	¥390M ($2.5M)
2023-04-20	SELL	unknown	三井住友トラスト・アセットマネジメント株式会社 Sumitomo Mitsui Trust Asset Management Co.,Ltd.	other	12.5M	¥1,870.66	-214.1%	¥325M ($2.1M)
2023-04-19	BUY	block_purchase	ノルウェー銀行(Norges Bank) Norges Bank	passive	18.2M	¥1,870.66	+214.1%	¥65M ($420K)
2023-03-23	BUY	block_purchase	ノルウェー銀行(Norges Bank) Norges Bank	passive	18.1M	¥1,777.66	+230.6%	¥185M ($1.2M)
2023-03-08	BUY	block_purchase	ノルウェー銀行(Norges Bank) Norges Bank	passive	18.0M	¥1,944	+202.3%	¥473M ($3.1M)
2023-01-30	BUY	Market Buy	MUFGセキュリティーズEMEA MUFG Securities EMEA plc	other	2.0M	¥1,891	+210.7%	¥3.8B ($24.8M)
2023-01-30	BUY	Market Buy	三菱UFJ信託銀行株式会社 Mitsubishi UFJ Financial Group Inc.	passive	12.8M	¥1,891	+210.7%	¥24.2B ($156.3M)
2023-01-30	BUY	Market Buy	三菱UFJモルガン・スタンレー証券株式会社 Mitsubishi UFJ Morgan Stanley Securities Co., Ltd.	other	1.0M	¥1,891	+210.7%	¥1.9B ($12.3M)
2023-01-30	BUY	Market Buy	三菱UFJ国際投信株式会社 Mitsubishi UFJ Financial Group Inc.	passive	3.1M	¥1,891	+210.7%	¥6.0B ($38.4M)
2022-12-19	BUY	Market Buy	三菱UFJモルガン・スタンレー証券株式会社 Mitsubishi UFJ Morgan Stanley Securities Co., Ltd.	other	75.3K	¥1,885.33	+211.7%	¥11.1B ($71.9M)
2022-12-19	BUY	Market Buy	三菱UFJ国際投信株式会社 Mitsubishi UFJ Financial Group Inc.	passive	3.1M	¥1,885.33	+211.7%	¥787M ($5.1M)
2022-12-19	BUY	Market Buy	MUFGセキュリティーズEMEA MUFG Securities EMEA plc	other	925.0K	¥1,885.33	+211.7%	¥1.7B ($11.3M)
2022-12-19	SELL	Market Buy	三菱UFJ信託銀行株式会社 Mitsubishi UFJ Financial Group Inc.	passive	13.1M	¥1,885.33	-211.7%	¥1.5B ($9.7M)
2022-12-06	SELL	Market Buy	日興アセットマネジメント株式会社 Nikko Asset Management Co.,Ltd.	other	6.2M	¥1,866.66	-214.8%	¥844M ($5.4M)
2022-12-06	BUY	Market Buy	三井住友トラスト・アセットマネジメント株式会社 Sumitomo Mitsui Trust Asset Management Co.,Ltd.	other	12.7M	¥1,866.66	+214.8%	¥65M ($419K)
2022-11-14	SELL	Market Buy	ノルウェー銀行(Norges Bank) Norges Bank	passive	17.8M	¥2,053.33	-186.2%	¥714M ($4.6M)
2022-09-13	BUY	block_purchase	ノルウェー銀行(Norges Bank) Norges Bank	passive	18.1M	¥2,026	+190.0%	¥986M ($6.4M)
2022-05-19	BUY	Market Buy	ブラックロック・ジャパン株式会社 BlackRock Japan Co., Ltd.	passive	6.6M	¥1,660.67	+253.8%	¥1.2B ($7.8M)
2022-05-19	SELL	Market Buy	ブラックロック・インベストメント・マネジメント(ユーケー)リミテッドLimited) BlackRock Investment Management (UK	passive	652.1K	¥1,660.67	-253.8%	¥346M ($2.2M)
2022-05-19	BUY	Market Buy	ブラックロック・インスティテューショナル・トラスト・カンパニー、エヌ.エイ.(BlackRock Institutional Trust Company BlackRock Institutional Trust Company, N.A.	passive	4.3M	¥1,660.67	+253.8%	¥7.2B ($46.3M)
2022-05-19	BUY	Market Buy	ブラックロック・ファンド・アドバイザーズ BlackRock Fund Advisors	passive	5.5M	¥1,660.67	+253.8%	¥1.6B ($10.4M)
2022-05-19	BUY	Market Buy	ブラックロック・アセット・マネジメント・アイルランド・リミテッド BlackRock Asset Management Ireland Limited	passive	2.5M	¥1,660.67	+253.8%	¥2.0B ($13.0M)
2022-05-19	BUY	Market Buy	ブラックロック・ライフ・リミテッド BlackRock Life Limited	passive	170.1K	¥1,660.67	+253.8%	¥28.3B ($182.5M)
2022-05-19	BUY	Market Buy	ブラックロック・ファンド・マネジャーズ・リミテッド BlackRock Fund Managers Limited	passive	962.0K	¥1,660.67	+253.8%	¥982M ($6.3M)
2022-05-19	BUY	Market Buy	ブラックロック(ネザーランド)BVBV) BlackRock (Netherlands	passive	1.1M	¥1,660.67	+253.8%	¥1.8B ($11.4M)

Showing the 50 most recent of 62 filings.

Frequently asked questions

Who has been buying Sompo Holdings, Inc. stock?: 26 distinct investors have filed 35 disclosed large-shareholding filings in Sompo Holdings, Inc. (8630), most recently on 2025-09-19. 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 Sompo Holdings, Inc. have?: Sompo Holdings, Inc. has 35 buy-side and 19 sell-side disclosures on record, covering ¥50.3B ($324.6M) in total reported value, spanning 2021-04-01 to 2025-09-19.
Where does StockDrifts get Sompo Holdings, 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 Sompo Holdings, Inc.. For how StockDrifts scores these disclosures, see the Japan insider signal tier research, or browse every Japanese stock we track.