TUSK insider buying and SEC filings, explained
Mammoth Energy Services, Inc. · CIK 1679268
Tracked: Forms 3/4/5, 8-K, NT · All filings on sec.gov
Insider activity in the last 12 months
Bought
$10.5M
Insiders who bought
3
Sold (not marked 10b5-1)
$0
Planned sales (10b5-1)
$0
Insider purchases and sales, last 12 months
| Traded | Type | What was filed | Source |
|---|---|---|---|
| Sep 16, 2026 | Purchase (code P) | Mark Lawrence Plaumann (Director) bought 5,000 shares at about $3.00 ($15K), reported as a purchase (code P). New position of 5,000 shares. Not marked as a 10b5-1 plan trade. | SEC filing Filed Sep 17, 2026 |
| Jun 17, 2026 | Purchase (code P) | Charles E. Davidson (Chief Business Officer and Director) bought 4,019,574 shares indirectly at $2.60 ($10.5M), reported as a purchase (code P). Indirect holdings up 61% to 10,620,789 shares. Not marked as a 10b5-1 plan trade. Filed jointly with 3 other reporting owners. | SEC filing Filed Jun 22, 2026 |
| Jun 11–12, 2026 | Purchase (code P) | Arthur H Amron (Director) bought 4,500 shares between Jun 11 and Jun 12 at about $3.25 ($15K), reported as a purchase (code P). Holdings up 7% to 67,135 shares. Not marked as a 10b5-1 plan trade. | SEC filing Filed Jun 15, 2026 |
| May 26–28, 2026 | Purchase (code P) | Arthur H Amron (Director) bought 5,500 shares between May 26 and May 28 at about $3.25 ($18K), reported as a purchase (code P). Holdings up 10% to 62,635 shares. Not marked as a 10b5-1 plan trade. | SEC filing Filed May 28, 2026 |
| Dec 11, 2025 | Purchase (code P) | Arthur H Amron (Director) bought 10,000 shares at $1.89 ($19K), reported as a purchase (code P). Holdings up 21% to 57,135 shares. Not marked as a 10b5-1 plan trade. | SEC filing Filed Dec 15, 2025 |
5 routine transactions (such as grants, option exercises or tax withholding) are not listed.
Cluster buys
2 insiders bought in 30 days
$10.5M in purchases since May 28, 2026 · Purchases traded May 28, 2026 to Jun 17, 2026 · Closed
| Insider | Value | Traded | Source |
|---|---|---|---|
| Arthur H Amron (Director) | $18K | May 28, 2026 | SEC filing |
| Arthur H Amron (Director) | $15K | Jun 12, 2026 | SEC filing |
| Charles E. Davidson (Chief Business Officer) | $10.5M | Jun 17, 2026 | SEC filing |
Red flags
No red flags in the last 12 months.
Key events
No key events in the last 12 months.
8-K filings, last 12 months
No 8-K filings in the last 12 months.
Red flags are objective triggers only: the item or form filed, never an opinion.
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