Dennis Thomas St

ACLS

Dennis Thomas St serves as director at Axcelis Technologies, Inc. (ACLS). This page tracks their complete SEC Form 4 insider trading history including stock purchases and sales.

Total Buys

1 trades

$54.0K

Total Sells

17 trades

$4.78M

Net Position

Net Seller

$4.73M

Companies Traded

ACLS, FORM, VECO

Active Period

Aug 2021 – May 2026

18 total trades

Most Recent

Sell ACLS

May 26, 2026 · $139.8K

Dennis Thomas St's Insider Trading at Axcelis Technologies, Inc. (ACLS)

Buys

0 · $0.00

Sells

5 · $2.29M

Total Shares Bought

Total Shares Sold

22,400

ACLS Price Chart

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Date	Type	Shares	Avg Price	Value	Shares After
May 26, 2026	Sell	900	$155.37	$139.8K	17,695
Feb 13, 2023	Sell	12,000	$127.02	$1.52M	0
Nov 18, 2022	Sell	3,000	$76.66	$230.0K	0
Feb 10, 2022	Sell	3,000	$72.81	$218.4K	0
Aug 30, 2021	Sell	3,500	$50.32	$176.1K	0

Dennis Thomas St's Insider Trading at FormFactor, Inc. (FORM)

Buys

0 · $0.00

Sells

9 · $2.06M

Total Shares Bought

Total Shares Sold

41,323

FORM Price Chart

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Date	Type	Shares	Avg Price	Value	Shares After
May 21, 2026	Sell	1,000	$115.84	$115.8K	31,873
Feb 11, 2026	Sell	7,431	$93.84	$697.4K	33,356
Nov 17, 2025	Sell	2,000	$49.85	$99.7K	38,957
May 30, 2025	Sell	3,000	$31.24	$93.7K	40,957
Nov 6, 2024	Sell	3,100	$39.11	$121.2K	37,429
May 13, 2024	Sell	2,000	$56.30	$112.6K	36,701
Nov 15, 2023	Sell	3,792	$38.24	$145.0K	38,701
Feb 17, 2023	Sell	13,000	$32.31	$420.0K	30,890
Feb 9, 2022	Sell	6,000	$41.63	$249.8K	40,098

Dennis Thomas St's Insider Trading at Veeco Instruments Inc. (VECO)

Buys

1 · $54.0K

Sells

3 · $437.4K

Total Shares Bought

2,500

Total Shares Sold

12,405

VECO Price Chart

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Date	Type	Shares	Avg Price	Value	Shares After
May 13, 2026	Sell	1,400	$61.93	$86.7K	61,697
May 14, 2024	Sell	4,000	$37.72	$150.9K	51,861
Dec 1, 2023	Sell	7,005	$28.52	$199.8K	52,184
May 17, 2022	Buy	2,500	$21.60	$54.0K	52,429