Who has been buying Science Arts, Inc. stock?

7 distinct investors have filed 10 disclosed large-shareholding filings in Science Arts, Inc. (4412), most recently on 2026-03-19. 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 Science Arts, Inc. have?

Science Arts, Inc. has 10 buy-side and 16 sell-side disclosures on record, covering ¥5.3B ($34.4M) in total reported value, spanning 2021-11-29 to 2026-03-19.

Where does StockDrifts get Science Arts, 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.

Science Arts, Inc. 4412

Company

株式会社サイエンスアーツScience Arts, Inc.

Investors

Buys

Total Value

¥5.3B ($34.4M)

Avg Return

+46.08%

Last Filing

2026-03-19

Science Arts, Inc. (4412) has 10 disclosed large-shareholding filings and 16 disclosed disposals on record, filed by 7 distinct investors. Together those filings cover ¥5.3B ($34.4M) in reported transaction value. The earliest filing StockDrifts holds for Science Arts, Inc. is dated 2021-11-29; the most recent is 2026-03-19. 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 +46.08%, 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
2026-03-19	BUY	negotiated	合同会社平岡秀一事務所	activist	3.0M	¥1,994	+18.0%	¥4.9B ($31.7M)
2026-03-19	SELL	negotiated	平岡秀一	activist	671.6K	¥1,994	+18.0%	¥1.1B ($7.1M)
2026-01-23	SELL	negotiated	合同会社平岡秀一事務所	activist	3.0M	¥2,144	+23.7%	¥4.9B ($31.7M)
2026-01-23	SELL	negotiated	平岡秀一	activist	743.6K	¥2,144	+23.7%	¥1.2B ($7.8M)
2025-04-23	BUY	negotiated	合同会社平岡秀一事務所 Shuichi Hiraoka LLC LLC	activist	3.0M	¥837	+95.5%	¥2.5B ($16.2M)
2025-04-23	SELL	negotiated	平岡秀一 Hiraoka Hidekazu	activist	838.0K	¥837	-95.5%	¥76M ($493K)
2025-01-22	SELL	negotiated	合同会社平岡秀一事務所 Shuichi Hiraoka LLC LLC	activist	3.0M	¥508	-222.1%	¥341M ($2.2M)
2025-01-22	SELL	negotiated	平岡秀一 Hiraoka Hidekazu	activist	929.8K	¥508	-222.1%	¥96M ($620K)
2024-11-06	BUY	Market Buy	楽天グループ株式会社 Rakuten Group, Inc.	passive	819.0K	¥572	+186.0%	¥468M ($3.0M)
2024-11-05	BUY	unknown	株式会社JVCケンウッド JVCKENWOOD Corporation	strategic	655.0K	¥560	+192.1%	¥367M ($2.4M)
2024-08-14	SELL	negotiated	合同会社平岡秀一事務所 Shuichi Hiraoka LLC LLC	activist	3.0M	¥504	-224.6%	¥1M ($7K)
2024-08-14	SELL	negotiated	平岡秀一 Hiraoka Hidekazu	activist	913.8K	¥504	-224.6%	¥30M ($197K)
2023-02-22	BUY	unknown	みずほ証券株式会社 Mizuho Securities Co., Ltd.	other	5.2K	¥757	+116.1%	¥188K ($1K)
2023-02-03	BUY	negotiated	合同会社平岡秀一事務所 Shuichi Hiraoka LLC LLC	activist	3.0M	¥870	+88.0%	¥2.6B ($16.8M)
2023-02-03	BUY	negotiated	平岡秀一 Hiraoka Hidekazu	activist	973.8K	¥870	+88.0%	¥847M ($5.5M)
2023-01-10	BUY	negotiated	合同会社平岡秀一事務所 Shuichi Hiraoka LLC LLC	activist	3.0M	¥881	+85.7%	¥2.6B ($17.1M)
2023-01-10	BUY	negotiated	平岡秀一 Hiraoka Hidekazu	activist	973.8K	¥881	+85.7%	¥858M ($5.5M)
2022-12-22	BUY	unknown	みずほ証券株式会社 Mizuho Securities Co., Ltd.	other	511.8K	¥877	+86.5%	¥449M ($2.9M)
2022-12-08	BUY	negotiated	合同会社平岡秀一事務所 Shuichi Hiraoka LLC LLC	activist	3.0M	¥978	+67.3%	¥2.9B ($18.9M)
2022-12-08	SELL	negotiated	平岡秀一 Hiraoka Hidekazu	activist	973.8K	¥978	-67.3%	¥58M ($377K)
2022-12-07	BUY	unknown	みずほ証券株式会社 Mizuho Securities Co., Ltd.	other	18.8K	¥986	+65.9%	¥14M ($88K)
2022-10-21	BUY	unknown	みずほ証券株式会社 Mizuho Securities Co., Ltd.	other	250.7K	¥1,122.5	+45.8%	¥281M ($1.8M)
2022-10-14	SELL	negotiated	平岡秀一 Hiraoka Hidekazu	activist	516.9K	¥1,242.5	-31.7%	¥18M ($113K)
2022-10-14	BUY	negotiated	合同会社平岡秀一事務所 Shuichi Hiraoka LLC LLC	activist	1.5M	¥1,242.5	+31.7%	¥1.9B ($12.0M)
2022-08-29	SELL	Market Buy	auカブコム証券株式会社 Mitsubishi UFJ Financial Group Inc.	passive	145.8K	¥1,290	-26.8%	¥70M ($452K)
2022-05-12	BUY	negotiated	合同会社平岡秀一事務所 Shuichi Hiraoka LLC LLC	activist	1.5M	¥1,075	+52.2%	¥1.6B ($10.4M)
2022-05-12	BUY	negotiated	合同会社平岡秀一事務所 Shuichi Hiraoka LLC LLC	activist	1.5M	¥1,075	+52.2%	¥1.6B ($10.4M)
2022-05-12	SELL	negotiated	平岡秀一 Hiraoka Hidekazu	activist	573.0K	¥1,075	-52.2%	¥51M ($326K)
2022-05-12	SELL	negotiated	平岡秀一 Hiraoka Hidekazu	activist	531.0K	¥1,075	-52.2%	¥45M ($291K)
2022-03-09	SELL	negotiated	SBテクノロジー株式会社 SB Technology Corp.	strategic	141.2K	¥1,515	-8.0%	¥127M ($817K)
2022-03-07	BUY	Market Buy	auカブコム証券株式会社 Mitsubishi UFJ Financial Group Inc.	passive	200.0K	¥1,970	-16.9%	¥394M ($2.5M)
2021-12-16	SELL	negotiated	平岡秀一 Hiraoka Hidekazu	activist	587.0K	¥6,900	+76.3%	¥227M ($1.5M)
2021-12-16	BUY	negotiated	合同会社平岡秀一事務所 Shuichi Hiraoka LLC LLC	activist	1.5M	¥6,900	-76.3%	¥10.3B ($66.8M)
2021-12-16	BUY	negotiated	合同会社平岡秀一事務所 Shuichi Hiraoka LLC LLC	activist	1.5M	¥6,900	-76.3%	¥10.3B ($66.8M)
2021-12-16	SELL	negotiated	平岡秀一 Hiraoka Hidekazu	activist	587.0K	¥6,900	+76.3%	¥227M ($1.5M)
2021-12-06	BUY	Market Buy	auカブコム証券株式会社 Mitsubishi UFJ Financial Group Inc.	passive	200.0K	¥4,560	-64.1%	¥912M ($5.9M)
2021-11-30	BUY	negotiated	SBテクノロジー株式会社 SB Technology Corp.	strategic	225.0K	¥3,880	-57.8%	¥873M ($5.6M)
2021-11-29	BUY	negotiated	合同会社平岡秀一事務所 Shuichi Hiraoka LLC LLC	activist	1.5M	¥3,625	-54.9%	¥5.4B ($35.1M)
2021-11-29	BUY	negotiated	平岡秀一 Hiraoka Hidekazu	activist	620.0K	¥3,625	-54.9%	¥2.2B ($14.5M)

Frequently asked questions

Who has been buying Science Arts, Inc. stock?: 7 distinct investors have filed 10 disclosed large-shareholding filings in Science Arts, Inc. (4412), most recently on 2026-03-19. 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 Science Arts, Inc. have?: Science Arts, Inc. has 10 buy-side and 16 sell-side disclosures on record, covering ¥5.3B ($34.4M) in total reported value, spanning 2021-11-29 to 2026-03-19.
Where does StockDrifts get Science Arts, 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 Science Arts, Inc.. For how StockDrifts scores these disclosures, see the Japan insider signal tier research, or browse every Japanese stock we track.