Summary
Updated Aug 31, 2026
Tzu Yin Chiu files SEC Form 4 reports at AXCELIS TECHNOLOGIES INC (ACLS). 2 SEC Form 4 filings on record going back to 2025, most recently on 18 May 2026.
Recent Transactions
2Every recent SEC Form 4 transaction Tzu Yin Chiu has reported, most recent first.
Trading Pattern
InsiderAlpha's records for Tzu Yin Chiu go back to 2025: 2 primary Form 4 filings, an average of 1.0 per year. No transaction on record carries a Rule 10b5-1 flag - the filings look discretionary rather than pre-scheduled, which makes their timing more informative as a signal.
Other Insiders Active in the Same Stocks
Insiders who reported open-market trades in the last 12 months at the companies Tzu Yin Chiu files at. Multiple unrelated insiders buying the same stock within a short window, cluster buying, has historically been one of the strongest Form 4 signals.
- Russell Low - $1.57M of ACLS open-market activity in the last 12 months
- Todd Sutton - $742K of ACLS open-market activity in the last 12 months
- Robert John Mahoney - $543K of ACLS open-market activity in the last 12 months
- John T. Kurtzweil - $486K of ACLS open-market activity in the last 12 months
- Greg Redinbo - $464K of ACLS open-market activity in the last 12 months
- Gregory B. Graves - $457K of ACLS open-market activity in the last 12 months
More Notable Insiders
Other corporate insiders with significant SEC Form 4 track records on InsiderAlpha:
- Christine Chivily
- Pad Chivukula
- Bruce R. Chizen
- Gerald M. Chizever
- Stefan Chkautovich
- CHLM Sponsor-5 LLC
- Chloe R. Seelbach, Trustee UAD 2/2/05 The Taplin Elizabeth Seelbach Trust
- Chloe R. Seelbach, Trustee under Claiborne Rankin Trust for Children of Chloe R. Seelbach DTD 12/21/04 FBO Isabelle Scott Seelbach
Frequently Asked Questions
Who is Tzu Yin Chiu?
Tzu Yin Chiu is a corporate insider of AXCELIS TECHNOLOGIES INC (ACLS). InsiderAlpha holds 2 primary Form 4 filings for them, the earliest from 2025, updated as new SEC EDGAR filings are processed.
When did Tzu Yin Chiu last file a Form 4?
The most recent primary Form 4 on record is dated 18 May 2026, one of 2 filings going back to 2025.
Where can I see all of Tzu Yin Chiu'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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