Mark Duff - Net Worth and Insider Trading
Mark Duff Net Worth
The estimated net worth of Mark Duff is at least $2 Million dollars as of 2026-08-09. Mark Duff is the President and CEO of Perma-Fix Environmental Services Inc and owns about 134,556 shares of Perma-Fix Environmental Services Inc (PESI) stock worth over $2 Million. Details can be seen in Mark Duff's Latest Holdings Summary section.
Disclaimer: The insider information is derived from SEC filings. The estimated net worth is based on the final shares held after open market or private purchases and sales of common stock with a transaction code of "P" or "S" on Form 4, assuming that Mark Duff has not made any transactions after 2025-09-11 and currently still holds the listed stock(s). Please note that this estimate may not reflect the actual net worth.
Transaction Summary of Mark Duff
Mark Duff Insider Ownership Reports
Based on ownership reports from SEC filings, as the reporting owner, Mark Duff owns 1 companies in total, including Perma-Fix Environmental Services Inc (PESI) .
Click here to see the complete history of Mark Duff’s form 4 insider trades.
Insider Ownership Summary of Mark Duff
| Ticker | Company | Transaction Date | Type of Owner |
|---|---|---|---|
| PESI | Perma-Fix Environmental Services Inc | 2025-09-11 | Executive Vice President/COO |
Mark Duff Latest Holdings Summary
Mark Duff currently owns a total of 1 stock. Mark Duff owns 134,556 shares of Perma-Fix Environmental Services Inc (PESI) as of September 11, 2025, with a value of $2 Million.
Latest Holdings of Mark Duff
| Ticker | Company | Latest Transaction Date | Shares Owned | Current Price ($) | Current Value ($) |
|---|---|---|---|---|---|
| PESI | Perma-Fix Environmental Services Inc | 2025-09-11 | 134,556 | 18.08 | 2,432,772 |
Holding Weightings of Mark Duff
Mark Duff Form 4 Trading Tracker
According to the SEC Form 4 filings, Mark Duff has made a total of 9 transactions in Perma-Fix Environmental Services Inc (PESI) over the past 5 years, including 9 buys and 0 sells. The most-recent trade in Perma-Fix Environmental Services Inc is the acquisition of 897 shares on September 11, 2025, which cost Mark Duff around $7,221.
Insider Trading History of Mark Duff
* The information on this page (including Insider Trading Shares, Share Changes, Cost, etc.) is sourced exclusively from Form 4 filings and does not incorporate any data from 13F or 13D/G filings. As a result, it may differ from the values shown on the Guru page.
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Mark Duff Trading Performance
GuruFocus tracks the stock performance after each of Mark Duff's buying transactions within different timeframes. To be detailed, the average return of stocks after 3 months bought by Mark Duff is 24.74%. GuruFocus also compares Mark Duff's trading performance to market benchmark return within the same time period. The performance of stocks bought by Mark Duff within 3 months outperforms 15 times out of 21 transactions in total compared to the return of S&P 500 within the same period.
You can select different timeframes to see how Mark Duff's insider trading performs compared to the benchmark.
Performance of Mark Duff
Average Return
Outperforming Transactions
| 1 Month | 3 Months | 6 Months | 1 Year | 2 Years | 3 Years | |
|---|---|---|---|---|---|---|
| Return(%) | 8.75 | | | | | |
| Relative Return to S&P 500(%) | 7.33 | | | | | |
Mark Duff Ownership Network
Ownership Network List of Mark Duff
Ownership Network Relation of Mark Duff
Mark Duff Owned Company Details
What does Perma-Fix Environmental Services Inc do?
Who are the key executives at Perma-Fix Environmental Services Inc?
Mark Duff is the Executive Vice President/COO of Perma-Fix Environmental Services Inc. Other key executives at Perma-Fix Environmental Services Inc include Chief Financial Officer Ben Naccarato , Chairman of Board & CEO Louis F Centofanti , and Chief Operating Officer Troy Eshleman .
Perma-Fix Environmental Services Inc (PESI) Insider Trades Summary
Over the past 18 months, Mark Duff made 3 insider transaction in Perma-Fix Environmental Services Inc (PESI) with a net purchase of 3,947. Other recent insider transactions involving Perma-Fix Environmental Services Inc (PESI) include a net purchase of 2,000 shares made by Larry Shelton , a net sale of 5,653 shares made by Kerry C Duggan , and a net purchase of 1,350 shares made by Troy Eshleman .
In summary, during the past 3 months, insiders sold 0 shares of Perma-Fix Environmental Services Inc (PESI) in total and bought 0 shares, with a net sale of 0 shares. During the past 18 months, 5,653 shares of Perma-Fix Environmental Services Inc (PESI) were sold and 8,697 shares were bought by its insiders, resulting in a net purchase of 3,044 shares.
Perma-Fix Environmental Services Inc (PESI)'s detailed insider trading history can be found in Insider Trading Tracker table.
Perma-Fix Environmental Services Inc Insider Transactions
Mark Duff Mailing Address
Above is the net worth, insider trading, and ownership report for Mark Duff. Based on the public information released on the U.S. Securities and Exchange Commission (SEC) website, Mark Duff's mailing address is: Atlanta Ga 30350.
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