Who has been buying Billing System Corporation stock?

5 distinct investors have filed 10 disclosed large-shareholding filings in Billing System Corporation (3623), most recently on 2026-03-03. 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 Billing System Corporation have?

Billing System Corporation has 10 buy-side and 7 sell-side disclosures on record, covering ¥1.5B ($9.6M) in total reported value, spanning 2023-05-15 to 2026-03-03.

Where does StockDrifts get Billing System Corporation 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.

Billing System Corporation 3623

Company

ビリングシステム株式会社Billing System Corporation

Investors

Buys

Total Value

¥1.5B ($9.6M)

Avg Return

-18.86%

Last Filing

2026-03-03

Billing System Corporation (3623) has 10 disclosed large-shareholding filings and 7 disclosed disposals on record, filed by 5 distinct investors. Together those filings cover ¥1.5B ($9.6M) in reported transaction value. The earliest filing StockDrifts holds for Billing System Corporation is dated 2023-05-15; the most recent is 2026-03-03. 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 -18.86%, 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
2026-03-03	BUY	unknown	オールド・ピーク・リミテッド Old Peak Limited	activist	0	¥1,100	+0.5%	-
2026-03-03	SELL	unknown	オールド・ピーク・グループ・リミテッド Old Peak Group Ltd.	activist	266.2K	¥1,100	+0.5%	¥291M ($1.9M)
2026-01-27	BUY	unknown	オールド・ピーク・リミテッド Old Peak Limited	activist	0	¥984	-11.3%	-
2026-01-27	SELL	unknown	オールド・ピーク・グループ・リミテッド Old Peak Group Ltd.	activist	331.9K	¥984	-11.3%	¥363M ($2.3M)
2025-12-01	BUY	Market Buy	オールド・ピーク・リミテッド Old Peak Limited	passive	0	¥1,009	-8.5%	-
2025-12-01	SELL	Market Buy	オールド・ピーク・グループ・リミテッド Old Peak Group Ltd.	passive	398.5K	¥1,009	-8.5%	¥436M ($2.8M)
2025-10-06	BUY	Market Buy	オールド・ピーク・リミテッド Old Peak Limited	passive	0	¥1,131	-3.2%	-
2025-10-06	SELL	Market Buy	オールド・ピーク・グループ・リミテッド Old Peak Group Ltd.	passive	466.6K	¥1,131	+3.2%	¥74M ($479K)
2024-10-02	BUY	Market Buy	オールド・ピーク・リミテッド Old Peak Limited	passive	0	¥1,366	-19.8%	-
2024-10-02	BUY	Market Buy	オールド・ピーク・グループ・リミテッド Old Peak Group Ltd.	passive	532.3K	¥1,366	-19.8%	¥96M ($619K)
2024-10-02	BUY	Market Buy	オールド・ピーク・グループ・リミテッド(Old Peak Group Ltd.). Old Peak Group Ltd.	passive	532.3K	¥1,366	-19.8%	¥96M ($619K)
2024-09-12	BUY	Market Buy	オールド・ピーク・グループ・リミテッド(Old Peak Group Ltd.). Old Peak Group Ltd.	passive	462.3K	¥1,808	-39.4%	¥208M ($1.3M)
2024-09-12	BUY	Market Buy	オールド・ピーク・リミテッド Old Peak Limited	passive	0	¥1,808	-39.4%	-
2024-09-12	BUY	Market Buy	オールド・ピーク・グループ・リミテッド Old Peak Group Ltd.	passive	462.3K	¥1,808	-39.4%	¥208M ($1.3M)
2024-09-12	BUY	Market Buy	オールド・ピーク・グループ・リミテッド(Old Peak Group Ltd.). Old Peak Group Ltd.	passive	462.3K	¥1,808	-39.4%	¥208M ($1.3M)
2024-09-02	BUY	Market Buy	オールド・ピーク・リミテッド Old Peak Limited	passive	0	¥1,652	-33.7%	-
2024-09-02	BUY	Market Buy	オールド・ピーク・グループ・リミテッド Old Peak Group Ltd.	passive	347.3K	¥1,652	-33.7%	¥574M ($3.7M)
2024-09-02	BUY	Market Buy	オールド・ピーク・グループ・リミテッド(Old Peak Group Ltd.). Old Peak Group Ltd.	passive	347.3K	¥1,652	-33.7%	¥574M ($3.7M)
2024-08-16	SELL	Market Buy	光通信株式会社 Hikari Tsushin K.K.	passive	324.1K	¥1,390	+21.2%	¥99M ($642K)
2024-06-04	BUY	Market Buy	光通信株式会社 Hikari Tsushin K.K.	passive	395.7K	¥1,050	+4.3%	¥70M ($449K)
2024-01-09	BUY	Market Buy	光通信株式会社 Hikari Tsushin K.K.	passive	329.3K	¥916	+19.5%	¥302M ($1.9M)
2023-07-10	SELL	unknown	株式会社NTTデータグループ NTT DATA GROUP CORPORATION	other	0	¥1,021	-7.3%	¥449M ($2.9M)
2023-07-10	BUY	unknown	株式会社NTTデータ NTT DATA JAPAN CORPORATION	other	440.0K	¥1,021	+7.3%	¥449M ($2.9M)
2023-07-10	BUY	unknown	株式会社NTTデータ NTT DATA JAPAN CORPORATION	other	440.0K	¥1,021	+7.3%	¥449M ($2.9M)
2023-07-10	BUY	unknown	株式会社NTTデータグループ NTT DATA GROUP CORPORATION	other	0	¥1,021	+7.3%	¥449M ($2.9M)
2023-05-15	SELL	unknown	株式会社エヌ・ティ・ティ・データ NTT DATA CORPORATION	other	440.0K	¥1,041	-5.2%	¥21M ($132K)

Frequently asked questions

Who has been buying Billing System Corporation stock?: 5 distinct investors have filed 10 disclosed large-shareholding filings in Billing System Corporation (3623), most recently on 2026-03-03. 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 Billing System Corporation have?: Billing System Corporation has 10 buy-side and 7 sell-side disclosures on record, covering ¥1.5B ($9.6M) in total reported value, spanning 2023-05-15 to 2026-03-03.
Where does StockDrifts get Billing System Corporation 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 Billing System Corporation. For how StockDrifts scores these disclosures, see the Japan insider signal tier research, or browse every Japanese stock we track.