David M Demski

ATEC

David M Demski serves as Director at Alphatec Holdings, Inc. (ATEC). This page tracks their complete SEC Form 4 insider trading history including stock purchases and sales.

Total Buys

3 trades

$860.9K

Total Sells

1 trades

$636.0K

Net Position

Net Buyer

$224.9K

Companies Traded

ATEC

Active Period

Nov 2023 – Dec 2025

4 total trades

Most Recent

Sell ATEC

Dec 11, 2025 · $636.0K

David M Demski's Insider Trading at Alphatec Holdings, Inc. (ATEC)

Buys

3 · $860.9K

Sells

1 · $636.0K

Total Shares Bought

120,000

Total Shares Sold

30,000

ATEC Price Chart

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Date	Type	Shares	Avg Price	Value
Dec 11, 2025	Sell	30,000	$21.20	$636.0K
Aug 21, 2024	Buy	50,000	$5.67	$283.5K
Aug 2, 2024	Buy	40,000	$6.56	$262.4K
Nov 9, 2023	Buy	30,000	$10.50	$315.0K

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