Who has been buying Philoptics stock?

9 distinct insiders have filed 4 disclosed insider purchases in Philoptics (161580), most recently on 2026-05-15. 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 Philoptics have?

Philoptics has 4 buy-side and 11 sell-side disclosures on record, covering ₩1.4B ($978K) in total reported value, spanning 2021-06-04 to 2026-05-15.

Where does StockDrifts get Philoptics insider data?

From DART D001/D002 insider disclosures — the official filing system run by the Financial Supervisory Service (Korea). StockDrifts parses each disclosure and matches it to daily price history; the original filings remain available directly from DART.

Do insider buys in Korean stocks predict returns?

Not uniformly. StockDrifts analysed 170,720 share-count changes across 56,930 Korean DART filings using cross-sectional alpha at fixed forward horizons, and found returns concentrated in particular signal tiers rather than in insider buying generally.

Philoptics 161580

Company

필옵틱스Philoptics

Insiders

Buys

Total Value

₩1.4B ($978K)

Avg Return

-8.85%

Last Filing

2026-05-15

Philoptics (161580) has 4 disclosed insider purchases and 11 disclosed disposals on record, filed by 9 distinct insiders. Together those filings cover ₩1.4B ($978K) in reported transaction value. The earliest filing StockDrifts holds for Philoptics is dated 2021-06-04; the most recent is 2026-05-15. All of it is parsed from DART D001/D002 insider disclosures, the official disclosure system operated by the Financial Supervisory Service (Korea). Across these filings the average return since disclosure is -8.85%, measured from each filing date to the latest available close.

Price & insider activity (12 months)

Recent insider trades

Date	Type	Source	Insider	Position	Shares	Price at filing	Return	Value
2026-05-15	SELL	Market Sell	임옥규 Lim Ok-gyu	Managing Director	-3.0K	₩49,000	+5.9%	₩147M ($102K)
2026-04-23	SELL	Market Sell	심상원 Sangwon Sim	moving	-1.6K	₩48,200	-2.4%	₩77M ($54K)
2026-04-22	SELL	Market Sell	한규완 Han Gyu-wan	vice president	-3.4K	₩50,700	+2.7%	₩172M ($120K)
2026-03-27	BUY	주식매수선택권	한규완 Han Gyu-wan	vice president	13.5K	₩39,500	+24.7%	₩533M ($370K)
2026-03-27	BUY	주식매수선택권	심상원 Sangwon Sim	moving	6.0K	₩39,500	+24.7%	₩237M ($165K)
2025-11-10	SELL	Market Sell	갈경수 Galgyeongsu	Managing Director	-2.0K	₩49,450	+1.3%	₩99M ($69K)
2025-11-06	SELL	Market Sell	이준호 Junho Lee	Managing Director	-1.0K	₩52,100	+6.3%	₩52M ($36K)
2025-11-05	SELL	Market Sell	유성주 Seongju Yoo	moving	-4.0K	₩52,900	+7.8%	₩212M ($147K)
2025-09-19	BUY	주식매수선택권	갈경수 Galgyeongsu	Managing Director	2.0K	₩36,300	+34.4%	₩73M ($50K)
2025-09-19	BUY	주식매수선택권	유성주 Seongju Yoo	moving	2.0K	₩36,300	+34.4%	₩73M ($50K)
2025-05-20	BUY	Market Buy	고은석 Go Eun-seok	Outside Director	1.1K	₩30,650	+59.2%	₩34M ($24K)
2025-05-12	BUY	Market Buy	고은석 Go Eun-seok	Outside Director	600	₩32,600	+49.7%	₩20M ($14K)
2025-05-09	BUY	Market Buy	고은석 Go Eun-seok	Outside Director	800	₩31,250	+56.2%	₩25M ($17K)
2025-05-08	BUY	Market Buy	고은석 Go Eun-seok	Outside Director	800	₩32,750	+49.0%	₩26M ($18K)
2025-03-31	SELL	Market Sell	임옥규 Lim Ok-gyu	Managing Director	-5.0K	₩33,300	-46.5%	₩167M ($116K)
2025-03-19	BUY	주식매수선택권	임옥규 Lim Ok-gyu	Managing Director	12.6K	₩40,600	+20.2%	₩510M ($354K)
2025-03-19	BUY	주식매수선택권	유성주 Seongju Yoo	moving	2.0K	₩40,600	+20.2%	₩81M ($56K)
2025-03-19	BUY	주식매수선택권	갈경수 Galgyeongsu	Managing Director	1.0K	₩40,600	+20.2%	₩41M ($28K)
2025-02-11	SELL	Market Sell	최정수 Jeongsoo Choi	moving	-1.0K	₩47,350	-3.1%	₩47M ($33K)
2025-02-01	BUY	신규선임	갈경수 Galgyeongsu	Managing Director	500	₩28,700	+70.0%	₩14M ($10K)
2025-01-13	SELL	Market Sell	한규완 Han Gyu-wan	vice president	-2.0K	₩24,400	-100.0%	₩49M ($34K)
2024-12-18	BUY	주식매수선택권	임옥규 Lim Ok-gyu	Managing Director	4.0K	₩20,600	+136.9%	₩82M ($57K)
2024-12-18	BUY	주식매수선택권	유성주 Seongju Yoo	moving	3.0K	₩20,600	+136.9%	₩62M ($43K)
2024-10-16	SELL	Market Sell	강상기 Kang Sang-gi	vice president	-10.8K	₩23,950	-103.8%	₩259M ($180K)
2024-07-12	BUY	주식매수선택권	임옥규 Lim Ok-gyu	Managing Director	7.0K	₩21,600	+125.9%	₩151M ($105K)
2024-07-12	BUY	주식매수선택권	한규완 Han Gyu-wan	vice president	3.0K	₩21,600	+125.9%	₩65M ($45K)
2024-07-04	SELL	Market Sell	한규완 Han Gyu-wan	vice president	-1.0K	₩22,700	-115.0%	₩23M ($16K)
2024-04-12	BUY	주식매수선택권	유성주 Seongju Yoo	moving	3.0K	₩25,100	+94.4%	₩75M ($52K)
2024-04-12	BUY	주식매수선택권	한규완 Han Gyu-wan	vice president	6.0K	₩25,100	+94.4%	₩151M ($105K)
2021-06-04	SELL	계약기간만료	임옥규 Lim Ok-gyu	Managing Director	-1.3K	₩11,600	-320.7%	₩16M ($11K)

Frequently asked questions

Who has been buying Philoptics stock?: 9 distinct insiders have filed 4 disclosed insider purchases in Philoptics (161580), most recently on 2026-05-15. 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 Philoptics have?: Philoptics has 4 buy-side and 11 sell-side disclosures on record, covering ₩1.4B ($978K) in total reported value, spanning 2021-06-04 to 2026-05-15.
Where does StockDrifts get Philoptics insider data?: From DART D001/D002 insider disclosures — the official filing system run by the Financial Supervisory Service (Korea). StockDrifts parses each disclosure and matches it to daily price history; the original filings remain available directly from DART.
Do insider buys in Korean stocks predict returns?: Not uniformly. StockDrifts analysed 170,720 share-count changes across 56,930 Korean DART filings using cross-sectional alpha at fixed forward horizons, and found returns concentrated in particular signal tiers rather than in insider buying generally.

Source filings

Every trade listed above is disclosed in DART D001/D002 insider disclosures, filed with the Financial Supervisory Service (Korea). View the original DART filings for Philoptics. For how StockDrifts scores these disclosures, see the Korea insider signal tier research, or browse every Korean stock we track.