Who has been buying letter stock?

1 distinct insiders have filed 27 disclosed insider purchases in letter (011370), most recently on 2025-08-18. 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 letter have?

letter has 27 buy-side and 1 sell-side disclosures on record, covering ₩1.1B ($775K) in total reported value, spanning 2024-03-29 to 2025-08-18.

Where does StockDrifts get letter 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.

letter 011370

Company

서한letter

Insiders

Buys

Total Value

₩1.1B ($775K)

Avg Return

+40.67%

Last Filing

2025-08-18

letter (011370) has 27 disclosed insider purchases and 1 disclosed disposals on record, filed by 1 distinct insiders. Together those filings cover ₩1.1B ($775K) in reported transaction value. The earliest filing StockDrifts holds for letter is dated 2024-03-29; the most recent is 2025-08-18. 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 +40.67%, 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
2026-08-10	BUY	시간외매매	김병준 Byeongjun Kim	Internal director	500.0K	₩755	+3.7%	₩355M ($247K)
2026-07-28	BUY	Market Buy	김병준 Byeongjun Kim	Internal director	3.8K	₩744	+5.2%	₩3M ($2K)
2026-07-28	BUY	Market Buy	김병준 Byeongjun Kim	Internal director	4.7K	₩744	+5.2%	₩4M ($3K)
2026-07-16	BUY	Market Buy	김병준 Byeongjun Kim	Internal director	4.6K	₩807	-3.0%	₩4M ($2K)
2026-07-15	BUY	Market Buy	김병준 Byeongjun Kim	Internal director	9.2K	₩805	-2.7%	₩7M ($5K)
2026-07-15	BUY	Market Buy	김병준 Byeongjun Kim	Internal director	10.1K	₩805	-2.7%	₩8M ($5K)
2026-07-15	BUY	Market Buy	김병준 Byeongjun Kim	Internal director	6.4K	₩805	-2.7%	₩5M ($3K)
2026-07-15	BUY	Market Buy	김병준 Byeongjun Kim	Internal director	109	₩805	-2.7%	₩86K ($60)
2026-07-14	BUY	Market Buy	김병준 Byeongjun Kim	Internal director	3.0K	₩795	-1.5%	₩2M ($2K)
2026-07-14	BUY	Market Buy	김병준 Byeongjun Kim	Internal director	3.5K	₩795	-1.5%	₩3M ($2K)
2026-07-13	BUY	Market Buy	김병준 Byeongjun Kim	Internal director	5.0K	₩782	+0.1%	₩4M ($3K)
2026-07-13	BUY	Market Buy	김병준 Byeongjun Kim	Internal director	5.0K	₩782	+0.1%	₩4M ($3K)
2026-07-09	BUY	Market Buy	김병준 Byeongjun Kim	Internal director	5.0K	₩803	-2.5%	₩4M ($3K)
2026-07-09	BUY	Market Buy	김병준 Byeongjun Kim	Internal director	814	₩803	-2.5%	₩685K ($475)
2026-07-09	BUY	Market Buy	김병준 Byeongjun Kim	Internal director	9.2K	₩803	-2.5%	₩8M ($5K)
2026-07-07	BUY	Market Buy	김병준 Byeongjun Kim	Internal director	2.6K	₩840	-6.8%	₩2M ($1K)
2026-07-07	BUY	Market Buy	김병준 Byeongjun Kim	Internal director	2.0K	₩840	-6.8%	₩2M ($1K)
2026-07-03	BUY	Market Buy	김병준 Byeongjun Kim	Internal director	4.4K	₩847	-7.6%	₩3M ($2K)
2025-08-18	SELL	시간외매매	정우필 Woopil Jeong	Internal director	-2.1M	₩928	-23.8%	₩1.9B ($1.3M)
2025-08-18	BUY	시간외매매	김병준 Byeongjun Kim	Internal director	2.1M	₩928	+23.8%	₩1.9B ($1.3M)
2025-01-23	BUY	Market Buy	김병준 Byeongjun Kim	Internal director	4.7K	₩786	+46.2%	₩4M ($3K)
2025-01-20	SELL	Market Sell	김병준 Byeongjun Kim	Internal director	-5	₩812	-41.5%	₩4K ($3)
2025-01-20	BUY	Market Buy	김병준 Byeongjun Kim	Internal director	19.1K	₩812	+41.5%	₩15M ($11K)
2025-01-16	BUY	Market Buy	김병준 Byeongjun Kim	Internal director	11.0K	₩820	+40.1%	₩9M ($6K)
2024-12-17	BUY	Market Buy	김병준 Byeongjun Kim	Internal director	5.0K	₩857	+34.1%	₩4M ($3K)
2024-12-12	BUY	Market Buy	김병준 Byeongjun Kim	Internal director	13.2K	₩817	+40.6%	₩11M ($7K)
2024-12-10	BUY	Market Buy	김병준 Byeongjun Kim	Internal director	9.6K	₩794	+44.7%	₩8M ($5K)
2024-12-09	BUY	Market Buy	김병준 Byeongjun Kim	Internal director	6.2K	₩760	+51.2%	₩5M ($3K)
2024-12-06	BUY	Market Buy	김병준 Byeongjun Kim	Internal director	8.1K	₩790	+45.4%	₩6M ($4K)
2024-12-05	BUY	Market Buy	김병준 Byeongjun Kim	Internal director	11.6K	₩795	+44.5%	₩9M ($6K)
2024-11-19	BUY	Market Buy	김병준 Byeongjun Kim	Internal director	1.8K	₩766	+50.0%	₩1M ($980)
2024-11-14	BUY	Market Buy	김병준 Byeongjun Kim	Internal director	17.5K	₩780	+47.3%	₩14M ($9K)
2024-11-11	BUY	Market Buy	김병준 Byeongjun Kim	Internal director	7.5K	₩784	+46.6%	₩6M ($4K)
2024-11-08	BUY	Market Buy	김병준 Byeongjun Kim	Internal director	10.0K	₩786	+46.2%	₩8M ($5K)
2024-11-07	BUY	Market Buy	김병준 Byeongjun Kim	Internal director	8.3K	₩804	+42.9%	₩7M ($5K)
2024-11-05	BUY	Market Buy	김병준 Byeongjun Kim	Internal director	16.0K	₩799	+43.8%	₩13M ($9K)
2024-11-01	BUY	Market Buy	김병준 Byeongjun Kim	Internal director	5.8K	₩765	+50.2%	₩4M ($3K)
2024-10-31	BUY	Market Buy	김병준 Byeongjun Kim	Internal director	23.0K	₩795	+44.5%	₩18M ($13K)
2024-10-14	BUY	Market Buy	김병준 Byeongjun Kim	Internal director	19.4K	₩809	+42.0%	₩16M ($11K)
2024-09-30	BUY	Market Buy	김병준 Byeongjun Kim	Internal director	10.0K	₩814	+41.1%	₩8M ($6K)
2024-09-24	BUY	Market Buy	김병준 Byeongjun Kim	Internal director	6.2K	₩806	+42.6%	₩5M ($3K)
2024-09-12	BUY	Market Buy	김병준 Byeongjun Kim	Internal director	12.5K	₩808	+42.2%	₩10M ($7K)
2024-09-11	BUY	Market Buy	김병준 Byeongjun Kim	Internal director	6.7K	₩801	+43.5%	₩5M ($4K)
2024-09-10	BUY	Market Buy	김병준 Byeongjun Kim	Internal director	7.0K	₩806	+42.6%	₩6M ($4K)
2024-08-19	BUY	Market Buy	김병준 Byeongjun Kim	Internal director	17.2K	₩804	+42.9%	₩14M ($10K)
2024-08-13	BUY	시간외매매	김병준 Byeongjun Kim	Internal director	2.2M	₩806	+42.6%	₩1.8B ($1.2M)
2024-08-13	SELL	시간외매매	조종수 driver	CEO	-2.2M	₩806	-42.6%	₩1.8B ($1.2M)
2024-08-09	BUY	Market Buy	김병준 Byeongjun Kim	Internal director	25.8K	₩818	+40.5%	₩21M ($15K)
2024-08-08	BUY	Market Buy	김병준 Byeongjun Kim	Internal director	23.0K	₩801	+43.5%	₩18M ($13K)
2024-07-09	BUY	Market Buy	김병준 Byeongjun Kim	Internal director	1.1M	₩823	+39.6%	₩871M ($605K)

Showing the 50 most recent of 51 filings.

Frequently asked questions

Who has been buying letter stock?: 1 distinct insiders have filed 27 disclosed insider purchases in letter (011370), most recently on 2025-08-18. 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 letter have?: letter has 27 buy-side and 1 sell-side disclosures on record, covering ₩1.1B ($775K) in total reported value, spanning 2024-03-29 to 2025-08-18.
Where does StockDrifts get letter 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 letter. For how StockDrifts scores these disclosures, see the Korea insider signal tier research, or browse every Korean stock we track.