Summary
Updated Aug 30, 2026
Sebastian Siemiatkowski is Chief Executive Officer, Director of Klarna Group plc (KLAR). 3 SEC Form 4 filings on record, most recently on 28 August 2026. Most recent open-market trade: bought $9.95M of KLAR on 28 August 2026. Lifetime open-market purchases: $9.95M.
Recent Transactions
1Every recent SEC Form 4 transaction Sebastian Siemiatkowski has reported, most recent first.
Most Active Insiders Right Now
Sebastian Siemiatkowski has no co-filers on record, so these are insiders with the largest open-market activity across the market in the last 90 days.
- Robert M. Williams Jr. - $268.34M of AVAH open-market activity in the last 90 days
- Henry Samueli - $250.01M of AVGO open-market activity in the last 90 days
- Mantle Ridge LP - $248.27M of DLTR open-market activity in the last 90 days
- ARES MANAGEMENT LLC - $235.75M of SVV open-market activity in the last 90 days
- J.H. Whitney Equity Partners VII, LLC - $232.77M of AVAH open-market activity in the last 90 days
- Control Empresarial de Capitales S.A. de C.V. - $230.75M of PBF open-market activity in the last 90 days
More Notable Insiders
Other corporate insiders with significant SEC Form 4 track records on InsiderAlpha:
Frequently Asked Questions
Who is Sebastian Siemiatkowski?
Sebastian Siemiatkowski is a corporate insider, tracked as Chief Executive Officer, Director of Klarna Group plc (KLAR). InsiderAlpha holds 3 primary Form 4 filings for them, the earliest from 2026, updated as new SEC EDGAR filings are processed.
How many SEC Form 4 filings has Sebastian Siemiatkowski submitted recently?
2 primary Form 4 filings in the last 90 days, covering 1 company.
Has Sebastian Siemiatkowski been buying or selling stock?
Recorded transactions: 1 open-market purchase ($9.95M) and 0 open-market sales across all tracked filings.
Where can I see all of Sebastian Siemiatkowski's SEC filings?
All Form 4 filings, transaction values, and 10b5-1 plan flags are listed on this page and updated in real time as new SEC EDGAR filings are processed.
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