WEXFORD CAPITAL LP

Insider Reports History

Reporting-owner location: West Palm Beach, FL
Latest reporting-owner signature: Wexford Capital LP, By: Wexford GP LLC, its general partner, By: Mark E. Ahern, Vice President and Assistant Secretary
Source: Latest parsed Forms 3/4/5 signature
Transaction source note: Rows are grouped by transaction date from the original SEC filing. Open the aggregated insider activity page to review issuer-level activity across dates.

Reported holdings for WEXFORD CAPITAL LP

Form 4 holding Chief Business Officer, Director, 10%+ Owner

MAMMOTH ENERGY SERVICES, INC.

Security class: Common Stock
Shares / value: 10,620,789
Estimated value: $27,659,720
Report date: 17 Jun 2026
Price: $2.60
Ownership: Indirect

Form 4 holding Chief Business Officer, Director, 10%+ Owner

MAMMOTH ENERGY SERVICES, INC.

Security class: Common Stock
Shares / value: 1,451,034
Estimated value: $3,555,033
Report date: 17 Jun 2026
Price: $2.45
Ownership: Direct

Form 4 holding 10%+ Owner

NEPHROS INC

Security class: Common Stock
Shares / value: 166,667
Estimated value: $595,001
Report date: 14 Sep 2026
Price: $3.57
Ownership: Indirect

Form 4 holding 10%+ Owner

NEPHROS INC

Security class: Common Stock
Shares / value: 56,872
Estimated value: $203,033
Report date: 18 Aug 2026
Price: $3.57
Ownership: Direct

Form 4 holding 10%+ Owner

NEPHROS INC

Security class: Stock Option (Right to Buy)
Shares / value: 36,198
Estimated value
Report date: 18 Aug 2026
Price
Ownership: Direct
Underlying class: Common Stock
Underlying amount

Insider Reports Filed by WEXFORD CAPITAL LP

4 NEPH

NEPHROS INC

Report period: 14 Sep 2026
Transactions: 2
Transaction value: $0
Accepted by SEC: 16 Sep 2026, 17:05
Role: 10%+ Owner
Next action: Open filing details

4 NEPH

NEPHROS INC

Report period: 18 Aug 2026
Transactions: 2
Transaction value: $0
Accepted by SEC: 20 Aug 2026, 16:14
Role: 10%+ Owner
Next action: Open filing details

4 TUSK

MAMMOTH ENERGY SERVICES, INC.

Report period: 17 Jun 2026
Transactions: 3
Transaction value: +$10,468,177
Accepted by SEC: 22 Jun 2026, 16:26
Role: Chief Business Officer, Director, 10%+ Owner
Next action: Open filing details

4 NEPH

NEPHROS INC

Report period: 13 Mar 2024
Transactions: 1
Transaction value: $0
Accepted by SEC: 14 Mar 2024, 16:43
Role: 10%+ Owner
Next action: Open filing details

4 TUSK

MAMMOTH ENERGY SERVICES, INC.

Report period: 12 Mar 2024
Transactions: 1
Transaction value: $0
Accepted by SEC: 14 Mar 2024, 16:22
Role: Director, 10%+ Owner
Next action: Open filing details

4 TUSK

MAMMOTH ENERGY SERVICES, INC.

Report period: 16 Jun 2022
Transactions: 2
Transaction value: +$96,977
Accepted by SEC: 21 Jun 2022, 16:32
Role: Director, 10%+ Owner
Next action: Open filing details

4 TUSK

MAMMOTH ENERGY SERVICES, INC.

Report period: 13 Jun 2022
Transactions: 3
Transaction value: +$117,346
Accepted by SEC: 15 Jun 2022, 16:37
Role: Director, 10%+ Owner
Next action: Open filing details

4 TUSK

MAMMOTH ENERGY SERVICES, INC.

Report period: 08 Jun 2022
Transactions: 3
Transaction value: +$241,381
Accepted by SEC: 10 Jun 2022, 16:34
Role: Director, 10%+ Owner
Next action: Open filing details

4 NEPH

NEPHROS INC

Report period: 01 Jun 2021
Transactions: 2
Transaction value: $0
Accepted by SEC: 03 Jun 2021, 16:41
Role: Director, 10%+ Owner
Next action: Open filing details

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