Insider trades › Thomas J. Seifert
Thomas J. Seifert
A corporate insider: an officer, director or owner of more than 10% of a company. Insiders report their trades to the SEC on Form 4The form insiders use to report each purchase or sale of their company's stock. It is due within two business days of the trade. · Last filing Oct 19, 2026
Companies
2
where this person reports as an insider
Open-market buys
0
among the latest 100 trades
Open-market sales
100
among the latest 100 trades
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Using 13F.ai, list Thomas J. Seifert's open-market buys and sells across companies in the last two years, with the Form 4 links.
Using 13F.ai, how did the stocks Thomas J. Seifert bought perform after the purchase compared with the S&P 500?
Using 13F.ai, are other insiders at the same companies buying or selling at the same time as Thomas J. Seifert?
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Buying and selling by quarter
Dollars bought and sold on the open market over the last two years.
Bought Sold
By trade date, using the shares and price reported for each trade. Stock grants, option exercises and shares withheld for tax are left out.
Roles
The companies where this person reports as an insider, and their position at each, most recent first.
Latest open-market trades
Purchases and sales at every company, most recent filing first.
| How the stock has done since the trade date, measured against the S&P 500 over the same days. It describes the stock, not the trader's actual gain or loss. | Filing | ||||||
|---|---|---|---|---|---|---|---|
| Oct 19, 2026 | NET Cloudflare, Inc. | Sale | 1,100 | $297.29 | $327.0K | +4.3% | Form 4 ↗ |
| Oct 19, 2026 | NET Cloudflare, Inc. | Sale | 500 | $304.15 | $152.1K | +4.3% | Form 4 ↗ |
| Oct 19, 2026 | NET Cloudflare, Inc. | Sale | 502 | $303.26 | $152.2K | +4.3% | Form 4 ↗ |
| Oct 19, 2026 | NET Cloudflare, Inc. | Sale | 598 | $301.99 | $180.6K | +4.3% | Form 4 ↗ |
| Oct 19, 2026 | NET Cloudflare, Inc. | Sale | 2,643 | $300.39 | $793.9K | +4.3% | Form 4 ↗ |
| Oct 19, 2026 | NET Cloudflare, Inc. | Sale | 3,756 | $299.36 | $1.1M | +4.3% | Form 4 ↗ |
| Oct 19, 2026 | NET Cloudflare, Inc. | Sale | 3,401 | $298.32 | $1.0M | +4.3% | Form 4 ↗ |
| Sep 17, 2026 | NET Cloudflare, Inc. | Sale | 100 | $318.90 | $31.9K | -7.3% | Form 4 ↗ |
| Sep 17, 2026 | NET Cloudflare, Inc. | Sale | 100 | $320.89 | $32.1K | -7.3% | Form 4 ↗ |
| Sep 17, 2026 | NET Cloudflare, Inc. | Sale | 100 | $326.56 | $32.7K | -7.3% | Form 4 ↗ |
| Sep 17, 2026 | NET Cloudflare, Inc. | Sale | 300 | $328.04 | $98.4K | -7.3% | Form 4 ↗ |
| Sep 17, 2026 | NET Cloudflare, Inc. | Sale | 700 | $329.37 | $230.6K | -7.3% | Form 4 ↗ |
| Sep 17, 2026 | NET Cloudflare, Inc. | Sale | 700 | $330.23 | $231.2K | -7.3% | Form 4 ↗ |
| Sep 17, 2026 | NET Cloudflare, Inc. | Sale | 1,196 | $331.59 | $396.6K | -7.3% | Form 4 ↗ |
| Sep 17, 2026 | NET Cloudflare, Inc. | Sale | 1,604 | $332.50 | $533.3K | -7.3% | Form 4 ↗ |
| Sep 17, 2026 | NET Cloudflare, Inc. | Sale | 2,632 | $333.62 | $878.1K | -7.3% | Form 4 ↗ |
| Sep 17, 2026 | NET Cloudflare, Inc. | Sale | 1,868 | $334.59 | $625.0K | -7.3% | Form 4 ↗ |
| Sep 17, 2026 | NET Cloudflare, Inc. | Sale | 600 | $335.32 | $201.2K | -7.3% | Form 4 ↗ |
| Sep 17, 2026 | NET Cloudflare, Inc. | Sale | 100 | $336.51 | $33.7K | -7.3% | Form 4 ↗ |
| Aug 17, 2026 | NET Cloudflare, Inc. | Sale | 900 | $305.25 | $274.7K | +2.0% | Form 4 ↗ |
| Aug 17, 2026 | NET Cloudflare, Inc. | Sale | 2,944 | $306.24 | $901.6K | +2.0% | Form 4 ↗ |
| Aug 17, 2026 | NET Cloudflare, Inc. | Sale | 2,456 | $307.29 | $754.7K | +2.0% | Form 4 ↗ |
| Aug 17, 2026 | NET Cloudflare, Inc. | Sale | 3,100 | $308.23 | $955.5K | +2.0% | Form 4 ↗ |
| Aug 17, 2026 | NET Cloudflare, Inc. | Sale | 300 | $309.07 | $92.7K | +2.0% | Form 4 ↗ |
| Aug 17, 2026 | NET Cloudflare, Inc. | Sale | 200 | $312.32 | $62.5K | +2.0% | Form 4 ↗ |
| Aug 17, 2026 | NET Cloudflare, Inc. | Sale | 100 | $314.61 | $31.5K | +2.0% | Form 4 ↗ |
| Aug 4, 2026 | NET Cloudflare, Inc. | Sale | 53,861 | $300.28 | $16.2M | +3.7% | Form 4 ↗ |
| Aug 4, 2026 | NET Cloudflare, Inc. | Sale | 1,139 | $301.00 | $342.8K | +3.7% | Form 4 ↗ |
| Jul 17, 2026 | NET Cloudflare, Inc. | Sale | 200 | $266.19 | $53.2K | +8.6% | Form 4 ↗ |
| Jul 17, 2026 | NET Cloudflare, Inc. | Sale | 100 | $267.76 | $26.8K | +8.6% | Form 4 ↗ |
| Jul 17, 2026 | NET Cloudflare, Inc. | Sale | 300 | $270.50 | $81.2K | +8.6% | Form 4 ↗ |
| Jul 17, 2026 | NET Cloudflare, Inc. | Sale | 500 | $274.60 | $137.3K | +8.6% | Form 4 ↗ |
| Jul 17, 2026 | NET Cloudflare, Inc. | Sale | 1,559 | $275.79 | $430.0K | +8.6% | Form 4 ↗ |
| Jul 17, 2026 | NET Cloudflare, Inc. | Sale | 1,741 | $276.63 | $481.6K | +8.6% | Form 4 ↗ |
| Jul 17, 2026 | NET Cloudflare, Inc. | Sale | 3,299 | $277.68 | $916.1K | +8.6% | Form 4 ↗ |
| Jul 17, 2026 | NET Cloudflare, Inc. | Sale | 1,201 | $278.76 | $334.8K | +8.6% | Form 4 ↗ |
| Jul 17, 2026 | NET Cloudflare, Inc. | Sale | 800 | $279.91 | $223.9K | +8.6% | Form 4 ↗ |
| Jul 17, 2026 | NET Cloudflare, Inc. | Sale | 300 | $281.29 | $84.4K | +8.6% | Form 4 ↗ |
| Jun 17, 2026 | NET Cloudflare, Inc. | Sale | 900 | $227.74 | $205.0K | +33.0% | Form 4 ↗ |
| Jun 17, 2026 | NET Cloudflare, Inc. | Sale | 900 | $228.91 | $206.0K | +33.0% | Form 4 ↗ |
| Jun 17, 2026 | NET Cloudflare, Inc. | Sale | 515 | $229.95 | $118.4K | +33.0% | Form 4 ↗ |
| Jun 17, 2026 | NET Cloudflare, Inc. | Sale | 685 | $230.90 | $158.2K | +33.0% | Form 4 ↗ |
| Jun 17, 2026 | NET Cloudflare, Inc. | Sale | 600 | $232.00 | $139.2K | +33.0% | Form 4 ↗ |
| Jun 17, 2026 | NET Cloudflare, Inc. | Sale | 3,167 | $233.44 | $739.3K | +33.0% | Form 4 ↗ |
| Jun 17, 2026 | NET Cloudflare, Inc. | Sale | 2,633 | $234.18 | $616.6K | +33.0% | Form 4 ↗ |
| Jun 17, 2026 | NET Cloudflare, Inc. | Sale | 600 | $235.34 | $141.2K | +33.0% | Form 4 ↗ |
| May 18, 2026 | NET Cloudflare, Inc. | Sale | 100 | $193.28 | $19.3K | +49.5% | Form 4 ↗ |
| May 18, 2026 | NET Cloudflare, Inc. | Sale | 300 | $195.14 | $58.5K | +49.5% | Form 4 ↗ |
| May 18, 2026 | NET Cloudflare, Inc. | Sale | 400 | $197.81 | $79.1K | +49.5% | Form 4 ↗ |
| May 18, 2026 | NET Cloudflare, Inc. | Sale | 928 | $199.05 | $184.7K | +49.5% | Form 4 ↗ |
| May 18, 2026 | NET Cloudflare, Inc. | Sale | 2,432 | $200.20 | $486.9K | +49.5% | Form 4 ↗ |
| May 18, 2026 | NET Cloudflare, Inc. | Sale | 3,570 | $201.21 | $718.3K | +49.5% | Form 4 ↗ |
| May 18, 2026 | NET Cloudflare, Inc. | Sale | 2,000 | $202.17 | $404.3K | +49.5% | Form 4 ↗ |
| May 18, 2026 | NET Cloudflare, Inc. | Sale | 270 | $203.02 | $54.8K | +49.5% | Form 4 ↗ |
| Apr 17, 2026 | NET Cloudflare, Inc. | Sale | 2,076 | $195.09 | $405.0K | +45.9% | Form 4 ↗ |
| Apr 17, 2026 | NET Cloudflare, Inc. | Sale | 1,724 | $196.04 | $338.0K | +45.9% | Form 4 ↗ |
| Apr 17, 2026 | NET Cloudflare, Inc. | Sale | 1,000 | $196.97 | $197.0K | +45.9% | Form 4 ↗ |
| Apr 17, 2026 | NET Cloudflare, Inc. | Sale | 600 | $198.04 | $118.8K | +45.9% | Form 4 ↗ |
| Apr 17, 2026 | NET Cloudflare, Inc. | Sale | 1,475 | $199.48 | $294.2K | +45.9% | Form 4 ↗ |
| Apr 17, 2026 | NET Cloudflare, Inc. | Sale | 2,725 | $200.51 | $546.4K | +45.9% | Form 4 ↗ |
| Apr 17, 2026 | NET Cloudflare, Inc. | Sale | 400 | $200.95 | $80.4K | +45.9% | Form 4 ↗ |
| Mar 17, 2026 | NET Cloudflare, Inc. | Sale | 200 | $207.68 | $41.5K | +32.1% | Form 4 ↗ |
| Mar 17, 2026 | NET Cloudflare, Inc. | Sale | 100 | $208.64 | $20.9K | +32.1% | Form 4 ↗ |
| Mar 17, 2026 | NET Cloudflare, Inc. | Sale | 3,041 | $211.69 | $643.7K | +32.1% | Form 4 ↗ |
| Mar 17, 2026 | NET Cloudflare, Inc. | Sale | 5,000 | $212.57 | $1.1M | +32.1% | Form 4 ↗ |
| Mar 17, 2026 | NET Cloudflare, Inc. | Sale | 2,000 | $213.23 | $426.5K | +32.1% | Form 4 ↗ |
| Feb 20, 2026 | NET Cloudflare, Inc. | Sale | 8,279 | $177.18 | $1.5M | +63.2% | Form 4 ↗ |
| Feb 20, 2026 | NET Cloudflare, Inc. | Sale | 4,700 | $178.53 | $839.1K | +63.2% | Form 4 ↗ |
| Feb 20, 2026 | NET Cloudflare, Inc. | Sale | 2,400 | $179.51 | $430.8K | +63.2% | Form 4 ↗ |
| Feb 20, 2026 | NET Cloudflare, Inc. | Sale | 1,900 | $180.68 | $343.3K | +63.2% | Form 4 ↗ |
| Feb 20, 2026 | NET Cloudflare, Inc. | Sale | 1,500 | $181.82 | $272.7K | +63.2% | Form 4 ↗ |
| Feb 20, 2026 | NET Cloudflare, Inc. | Sale | 1,300 | $182.53 | $237.3K | +63.2% | Form 4 ↗ |
| Feb 20, 2026 | NET Cloudflare, Inc. | Sale | 1,000 | $183.78 | $183.8K | +63.2% | Form 4 ↗ |
| Feb 20, 2026 | NET Cloudflare, Inc. | Sale | 100 | $195.19 | $19.5K | +63.2% | Form 4 ↗ |
| Feb 20, 2026 | NET Cloudflare, Inc. | Sale | 700 | $185.09 | $129.6K | +63.2% | Form 4 ↗ |
| Feb 20, 2026 | NET Cloudflare, Inc. | Sale | 500 | $186.10 | $93.0K | +63.2% | Form 4 ↗ |
| Feb 20, 2026 | NET Cloudflare, Inc. | Sale | 200 | $187.39 | $37.5K | +63.2% | Form 4 ↗ |
| Feb 20, 2026 | NET Cloudflare, Inc. | Sale | 300 | $188.77 | $56.6K | +63.2% | Form 4 ↗ |
| Feb 20, 2026 | NET Cloudflare, Inc. | Sale | 2,613 | $190.35 | $497.4K | +63.2% | Form 4 ↗ |
| Feb 20, 2026 | NET Cloudflare, Inc. | Sale | 8,133 | $191.13 | $1.6M | +63.2% | Form 4 ↗ |
| Feb 20, 2026 | NET Cloudflare, Inc. | Sale | 4,771 | $192.18 | $916.9K | +63.2% | Form 4 ↗ |
| Feb 20, 2026 | NET Cloudflare, Inc. | Sale | 2,766 | $193.12 | $534.2K | +63.2% | Form 4 ↗ |
| Feb 20, 2026 | NET Cloudflare, Inc. | Sale | 395 | $194.05 | $76.6K | +63.2% | Form 4 ↗ |
| Jan 20, 2026 | NET Cloudflare, Inc. | Sale | 928 | $176.27 | $163.6K | +61.0% | Form 4 ↗ |
| Jan 20, 2026 | NET Cloudflare, Inc. | Sale | 3,472 | $177.17 | $615.1K | +61.0% | Form 4 ↗ |
| Jan 20, 2026 | NET Cloudflare, Inc. | Sale | 1,800 | $178.08 | $320.5K | +61.0% | Form 4 ↗ |
| Jan 20, 2026 | NET Cloudflare, Inc. | Sale | 1,200 | $179.41 | $215.3K | +61.0% | Form 4 ↗ |
| Jan 20, 2026 | NET Cloudflare, Inc. | Sale | 1,900 | $180.09 | $342.2K | +61.0% | Form 4 ↗ |
| Jan 20, 2026 | NET Cloudflare, Inc. | Sale | 600 | $181.27 | $108.8K | +61.0% | Form 4 ↗ |
| Jan 20, 2026 | NET Cloudflare, Inc. | Sale | 100 | $181.98 | $18.2K | +61.0% | Form 4 ↗ |
| Dec 22, 2025 | NET Cloudflare, Inc. | Sale | 353 | $198.64 | $70.1K | +41.2% | Form 4 ↗ |
| Dec 22, 2025 | NET Cloudflare, Inc. | Sale | 1,000 | $200.58 | $200.6K | +41.2% | Form 4 ↗ |
| Dec 22, 2025 | NET Cloudflare, Inc. | Sale | 4,836 | $201.52 | $974.6K | +41.2% | Form 4 ↗ |
| Dec 22, 2025 | NET Cloudflare, Inc. | Sale | 3,328 | $202.37 | $673.5K | +41.2% | Form 4 ↗ |
| Dec 22, 2025 | NET Cloudflare, Inc. | Sale | 483 | $203.35 | $98.2K | +41.2% | Form 4 ↗ |
| Nov 20, 2025 | NET Cloudflare, Inc. | Sale | 2,725 | $193.50 | $527.3K | +44.2% | Form 4 ↗ |
| Nov 20, 2025 | NET Cloudflare, Inc. | Sale | 2,272 | $190.31 | $432.4K | +44.2% | Form 4 ↗ |
| Nov 20, 2025 | NET Cloudflare, Inc. | Sale | 13,331 | $191.45 | $2.6M | +44.2% | Form 4 ↗ |
| Nov 20, 2025 | NET Cloudflare, Inc. | Sale | 8,666 | $192.47 | $1.7M | +44.2% | Form 4 ↗ |
| Nov 20, 2025 | NET Cloudflare, Inc. | Sale | 1,900 | $194.34 | $369.2K | +44.2% | Form 4 ↗ |
Each row links to its Form 4. Since trade compares the stock’s move from the close on the trade date (or the next trading day) to its latest close with the S&P 500 over the same days, adjusted for splits and excluding dividends. It describes the stock, not what the trader made: we don’t know their purchase price, position size or later sales. A dash means the trade isn’t matched to a listed stock, or there is no closing price after it yet.
When several people report on the same filing, we list it under the first one named, so trades by someone usually listed second may be missing here. Information, not investment advice: see the disclaimer.