Who has been buying Shinagawa Refractories Co., Ltd. stock?

3 distinct investors have filed 2 disclosed large-shareholding filings in Shinagawa Refractories Co., Ltd. (5351), most recently on 2025-08-21. 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 Shinagawa Refractories Co., Ltd. have?

Shinagawa Refractories Co., Ltd. has 2 buy-side and 6 sell-side disclosures on record, covering ¥17M ($113K) in total reported value, spanning 2023-03-06 to 2025-08-21.

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.

Shinagawa Refractories Co., Ltd. 5351

Company

品川リフラクトリーズ株式会社Shinagawa Refractories Co., Ltd.

Investors

Buys

Total Value

¥17M ($113K)

Avg Return

+116.09%

Last Filing

2025-08-21

Shinagawa Refractories Co., Ltd. (5351) has 2 disclosed large-shareholding filings and 6 disclosed disposals on record, filed by 3 distinct investors. Together those filings cover ¥17M ($113K) in reported transaction value. The earliest filing StockDrifts holds for Shinagawa Refractories Co., Ltd. is dated 2023-03-06; the most recent is 2025-08-21. Across these filings the average return since disclosure is +116.09%, 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
2025-08-21	SELL	negotiated	三井住友信託銀行株式会社 Sumitomo Mitsui Trust Bank,Limited	strategic	980.4K	¥1,914	-6.0%	¥812M ($5.2M)
2025-08-21	SELL	negotiated	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	599.8K	¥1,914	-6.0%	¥99M ($640K)
2025-08-21	SELL	negotiated	日興アセットマネジメント株式会社 Nikko Asset Management Co.,Ltd.	other	353.0K	¥1,914	-6.0%	¥9M ($58K)
2024-02-06	SELL	negotiated	三井住友信託銀行株式会社 Sumitomo Mitsui Trust Bank,Limited	strategic	1.4M	¥2,023	-0.3%	¥467M ($3.0M)
2024-02-06	SELL	negotiated	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	652.9K	¥2,023	-0.3%	¥544M ($3.5M)
2024-02-06	SELL	negotiated	日興アセットマネジメント株式会社 Nikko Asset Management Co.,Ltd.	other	359.3K	¥2,023	-0.3%	¥124M ($800K)
2023-03-06	BUY	negotiated	三井住友信託銀行株式会社 Sumitomo Mitsui Trust Bank,Limited	strategic	326.8K	¥926	-	-
2023-03-06	BUY	negotiated	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	183.7K	¥926	+119.1%	¥71M ($456K)
2023-03-06	BUY	negotiated	日興アセットマネジメント株式会社 Nikko Asset Management Co.,Ltd.	other	83.7K	¥926	+119.1%	¥17M ($113K)

Frequently asked questions

Who has been buying Shinagawa Refractories Co., Ltd. stock?: 3 distinct investors have filed 2 disclosed large-shareholding filings in Shinagawa Refractories Co., Ltd. (5351), most recently on 2025-08-21. 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 Shinagawa Refractories Co., Ltd. have?: Shinagawa Refractories Co., Ltd. has 2 buy-side and 6 sell-side disclosures on record, covering ¥17M ($113K) in total reported value, spanning 2023-03-06 to 2025-08-21.
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.