WEXFORD CAPITAL LP

Insider · 10% owner · NEPH

WEXFORD CAPITAL LP files insider transactions with the SEC as a 10% owner of Nephros (NEPH). We hold 1 disclosed purchase or sale filed since 31 March 2006, 1 of them in the last 90 days.

Files forNEPH
Disclosed buys and sells1 in all, 1 in the last 90 days
Last disclosure20 August 2026

Positions held

13 posts we hold — a term names its own dates; a run of filings only says when they filed

Filed 1 June 2021 — 18 August 202610% owner · Nephros (NEPH)4 Form 4 lines · source: SEC Form 4
Filed 29 June 2018 — 17 June 2026Chief Business Officer · Mammoth Energy Services (TUSK)8 Form 4 lines · source: SEC Form 4
Filed 3 November 2011 — 31 December 2015Director and 10% owner · Rhino Resource Partners LP (RNO)11 Form 4 lines · source: SEC Form 4
Filed 5 July 2013 — 9 December 2015Director · Diamondback Energy (FANG)25 Form 4 lines · source: SEC Form 4
Filed 18 December 2014 — 22 December 201410% owner · Rlj Entertainment (RLJE)3 Form 4 lines · source: SEC Form 4
Filed 4 October 2013 — 4 October 2013Other role · Arno Therapeutics (ARNI)1 Form 4 line · source: SEC Form 4
Filed 27 March 2013 — 31 May 2013Other role · Epl Oil & Gas (EPL)8 Form 4 lines · source: SEC Form 4
Filed 17 December 2012 — 20 December 201210% owner · Empeiria Acquisition (EPAQU)4 Form 4 lines · source: SEC Form 4
Filed 29 March 2006 — 9 July 200910% owner · Bronco Drilling Company (BRNC)30 Form 4 lines · source: SEC Form 4
Filed 26 November 2008 — 26 November 200810% owner · Icx Technologies (ICXT)1 Form 4 line · source: SEC Form 4
Filed 13 May 2008 — 13 May 2008Other role · Javelin Pharmaceuticals (JAV)2 Form 4 lines · source: SEC Form 4
Filed 14 November 2007 — 14 November 200710% owner · Nephros (NEP)3 Form 4 lines · source: SEC Form 4
Filed 3 May 2006 — 3 May 2006Other role · Gulfport Energy (GPOR)7 Form 4 lines · source: SEC Form 4

Everything they disclosed

107 entries, newest first — one per disclosure report, one per Form 4 line

exercised options over 812 shares of NephrosSEC Form 420 August 2026Common Stock · traded 18 August 2026 · filed 20 August 2026
exercised options over 3,765 shares of Nephros (a derivative holding)SEC Form 420 August 2026Stock Option (Right to Buy) · traded 18 August 2026 · filed 20 August 2026
acquired or disposed of, other 1,072,896 shares of Mammoth Energy ServicesSEC Form 422 June 2026Common Stock · traded 17 June 2026 · filed 22 June 2026
acquired or disposed of, other 6,354,667 shares of Mammoth Energy ServicesSEC Form 422 June 2026Common Stock · traded 17 June 2026 · filed 22 June 2026
▲ bought on the open market 4,019,574 shares of Mammoth Energy ServicesSEC Form 422 June 2026Common Stock · traded 17 June 2026 · filed 22 June 2026
▲ bought on the open market 35,000 shares of Mammoth Energy ServicesSEC Form 421 June 2022Common Stock · traded 16 June 2022 · filed 21 June 2022
▲ bought on the open market 10,382 shares of Mammoth Energy ServicesSEC Form 421 June 2022Common Stock · traded 17 June 2022 · filed 21 June 2022
exercised in-the-money options over 66,667 shares of NephrosSEC Form 43 June 2021Common Stock · traded 1 June 2021 · filed 3 June 2021
exercised in-the-money options over 66,667 shares of Nephros (a derivative holding)SEC Form 43 June 2021Common Stock Warrants · traded 1 June 2021 · filed 3 June 2021
▲ bought on the open market 35,904 shares of Mammoth Energy ServicesSEC Form 415 November 2019Common Stock · traded 13 November 2019 · filed 15 November 2019
▼ sold on the open market 266,026 shares of Mammoth Energy ServicesSEC Form 41 August 2018Common Stock · traded 30 July 2018 · filed 1 August 2018
▼ sold on the open market 2,764,400 shares of Mammoth Energy ServicesSEC Form 43 July 2018Common Stock · traded 29 June 2018 · filed 3 July 2018
acquired or disposed of, other 2,222,779 shares of Rhino Resource Partners LPSEC Form 45 January 2016Common Units · traded 31 December 2015 · filed 5 January 2016
acquired or disposed of, other 6,793 shares of Rhino Resource Partners LPSEC Form 45 January 2016Common Units · traded 31 December 2015 · filed 5 January 2016
acquired or disposed of, other 3,179,613 shares of Rhino Resource Partners LP (a derivative holding)SEC Form 45 January 2016Subordinated Units · traded 31 December 2015 · filed 5 January 2016
acquired or disposed of, other 9,719 shares of Rhino Resource Partners LP (a derivative holding)SEC Form 45 January 2016Subordinated Units · traded 31 December 2015 · filed 5 January 2016
▼ sold on the open market 9,822 shares of Diamondback EnergySEC Form 410 December 2015Common Stock, par value $0.01 · traded 9 December 2015 · filed 10 December 2015
▼ sold on the open market 70,000 shares of Diamondback EnergySEC Form 422 September 2015Common Stock, par value $0.01 · traded 18 September 2015 · filed 22 September 2015
▼ sold on the open market 7,579 shares of Diamondback EnergySEC Form 417 September 2015Common Stock, par value $0.01 · traded 15 September 2015 · filed 17 September 2015
▼ sold on the open market 216,135 shares of Diamondback EnergySEC Form 417 September 2015Common Stock, par value $0.01 · traded 16 September 2015 · filed 17 September 2015
▼ sold on the open market 105,100 shares of Diamondback EnergySEC Form 417 September 2015Common Stock, par value $0.01 · traded 17 September 2015 · filed 17 September 2015
▼ sold on the open market 242,671 shares of Diamondback EnergySEC Form 424 March 2015Common Stock, par value $0.01 · traded 20 March 2015 · filed 24 March 2015
▼ sold on the open market 300,000 shares of Diamondback EnergySEC Form 49 March 2015Common Stock, par value $0.01 · traded 5 March 2015 · filed 9 March 2015
▼ sold on the open market 16,900 shares of Diamondback EnergySEC Form 49 March 2015Common Stock, par value $0.01 · traded 6 March 2015 · filed 9 March 2015
▼ sold on the open market 125,795 shares of Diamondback EnergySEC Form 44 March 2015Common Stock, par value $0.01 · traded 2 March 2015 · filed 4 March 2015
▼ sold on the open market 450,000 shares of Diamondback EnergySEC Form 44 March 2015Common Stock, par value $0.01 · traded 3 March 2015 · filed 4 March 2015
▼ sold on the open market 525,960 shares of Diamondback EnergySEC Form 44 March 2015Common Stock, par value $0.01 · traded 4 March 2015 · filed 4 March 2015
▼ sold on the open market 194,412 shares of Diamondback EnergySEC Form 428 January 2015Common Stock, par value $0.01 · traded 23 January 2015 · filed 28 January 2015
▼ sold on the open market 539,941 shares of Diamondback EnergySEC Form 428 January 2015Common Stock, par value $0.01 · traded 26 January 2015 · filed 28 January 2015
▼ sold on the open market 291,189 shares of Diamondback EnergySEC Form 428 January 2015Common Stock, par value $0.01 · traded 27 January 2015 · filed 28 January 2015
▼ sold on the open market 4,522 shares of Rlj EntertainmentSEC Form 422 December 2014Common Stock, par value $0.001 · traded 18 December 2014 · filed 22 December 2014
▼ sold on the open market 3,289 shares of Rlj EntertainmentSEC Form 422 December 2014Common Stock, par value $0.001 · traded 19 December 2014 · filed 22 December 2014
▼ sold on the open market 3,743 shares of Rlj EntertainmentSEC Form 422 December 2014Common Stock, par value $0.001 · traded 22 December 2014 · filed 22 December 2014
▼ sold on the open market 5,200 shares of Diamondback EnergySEC Form 417 March 2014Common Stock, par value $0.01 · traded 13 March 2014 · filed 17 March 2014
▼ sold on the open market 5,059 shares of Diamondback EnergySEC Form 417 March 2014Common Stock, par value $0.01 · traded 14 March 2014 · filed 17 March 2014
▼ sold on the open market 23,414 shares of Diamondback EnergySEC Form 417 March 2014Common Stock, par value $0.01 · traded 17 March 2014 · filed 17 March 2014
▼ sold on the open market 50,000 shares of Diamondback EnergySEC Form 43 March 2014Common Stock, par value $0.01 · traded 27 February 2014 · filed 3 March 2014
▼ sold on the open market 2,500 shares of Diamondback EnergySEC Form 43 March 2014Common Stock, par value $0.01 · traded 28 February 2014 · filed 3 March 2014
▼ sold on the open market 62,108 shares of Diamondback EnergySEC Form 43 March 2014Common Stock, par value $0.01 · traded 3 March 2014 · filed 3 March 2014
▼ sold on the open market 20,000 shares of Diamondback EnergySEC Form 429 November 2013Common Stock, par value $0.01 · traded 26 November 2013 · filed 29 November 2013
▼ sold on the open market 616,287 shares of Diamondback EnergySEC Form 415 November 2013Common Stock, par value $0.01 · traded 13 November 2013 · filed 15 November 2013
▼ sold on the open market 84,000 shares of Diamondback EnergySEC Form 415 November 2013Common Stock, par value $0.01 · traded 14 November 2013 · filed 15 November 2013
▼ sold on the open market 48,400 shares of Diamondback EnergySEC Form 415 November 2013Common Stock, par value $0.01 · traded 15 November 2013 · filed 15 November 2013
▼ sold on the open market 325 shares of Arno TherapeuticsSEC Form 49 October 2013Common Stock · traded 4 October 2013 · filed 9 October 2013
▼ sold on the open market 586,467 shares of Diamondback EnergySEC Form 49 July 2013Common Stock, par value $0.01 · traded 5 July 2013 · filed 9 July 2013
▼ sold on the open market 30,039 shares of Epl Oil & GasSEC Form 431 May 2013Common Stock, par value $0.001 · traded 29 May 2013 · filed 31 May 2013
▼ sold on the open market 100,000 shares of Epl Oil & GasSEC Form 431 May 2013Common Stock, par value $0.001 · traded 30 May 2013 · filed 31 May 2013
▼ sold on the open market 83,328 shares of Epl Oil & GasSEC Form 431 May 2013Common Stock, par value $0.001 · traded 31 May 2013 · filed 31 May 2013
▼ sold on the open market 137,400 shares of Epl Oil & GasSEC Form 413 May 2013Common Stock, par value $0.001 · traded 9 May 2013 · filed 13 May 2013
▼ sold on the open market 115,238 shares of Epl Oil & GasSEC Form 413 May 2013Common Stock, par value $0.001 · traded 10 May 2013 · filed 13 May 2013
▼ sold on the open market 130,568 shares of Epl Oil & GasSEC Form 413 May 2013Common Stock, par value $0.001 · traded 13 May 2013 · filed 13 May 2013
acquired or disposed of, other 5,744 shares of Rhino Resource Partners LP (a derivative holding)SEC Form 44 April 2013Subordinated Units · traded 31 March 2013 · filed 4 April 2013
acquired or disposed of, other 4,016 shares of Rhino Resource Partners LPSEC Form 44 April 2013Common Units · traded 31 March 2013 · filed 4 April 2013
▼ sold on the open market 50,000 shares of Epl Oil & GasSEC Form 428 March 2013Common Stock, par value $0.001 · traded 27 March 2013 · filed 28 March 2013
▼ sold on the open market 5,606 shares of Epl Oil & GasSEC Form 428 March 2013Common Stock, par value $0.001 · traded 28 March 2013 · filed 28 March 2013
acquired or disposed of, other 750,000 shares of Empeiria AcquisitionSEC Form 44 January 2013Common Stock · traded 17 December 2012 · filed 4 January 2013
acquired or disposed of, other 250,000 shares of Empeiria AcquisitionSEC Form 44 January 2013Common Stock · traded 17 December 2012 · filed 4 January 2013
▼ sold on the open market 107,300 shares of Empeiria Acquisition (a derivative holding)SEC Form 44 January 2013Warrants · traded 20 December 2012 · filed 4 January 2013
▼ sold on the open market 35,700 shares of Empeiria Acquisition (a derivative holding)SEC Form 44 January 2013Warrants · traded 20 December 2012 · filed 4 January 2013
acquired or disposed of, other 31,717 shares of Rhino Resource Partners LP (a derivative holding)SEC Form 46 March 2012Subordinated Units · traded 29 February 2012 · filed 6 March 2012
acquired or disposed of, other 22,169 shares of Rhino Resource Partners LPSEC Form 46 March 2012Common Units · traded 29 February 2012 · filed 6 March 2012
acquired or disposed of, other 1,294,060 shares of Rhino Resource Partners LP (a derivative holding)SEC Form 44 January 2012Subordinated Units · traded 30 December 2011 · filed 4 January 2012
acquired or disposed of, other 904,645 shares of Rhino Resource Partners LPSEC Form 44 January 2012Common Units · traded 30 December 2011 · filed 4 January 2012
was granted 6,130 shares of Rhino Resource Partners LPSEC Form 44 January 2012Common Units · traded 3 November 2011 · filed 4 January 2012
▼ sold on the open market 2,351 shares of Bronco Drilling CompanySEC Form 49 July 2009Common Stock, par value $0.01 · traded 7 July 2009 · filed 9 July 2009
▼ sold on the open market 1,349 shares of Bronco Drilling CompanySEC Form 49 July 2009Common Stock, par value $0.01 · traded 7 July 2009 · filed 9 July 2009
▼ sold on the open market 9,974 shares of Bronco Drilling CompanySEC Form 49 July 2009Common Stock, par value $0.01 · traded 9 July 2009 · filed 9 July 2009
▼ sold on the open market 5,726 shares of Bronco Drilling CompanySEC Form 49 July 2009Common Stock, par value $0.01 · traded 9 July 2009 · filed 9 July 2009
▼ sold on the open market 11,001 shares of Bronco Drilling CompanySEC Form 46 July 2009Common Stock, par value $0.01 · traded 1 July 2009 · filed 6 July 2009
▼ sold on the open market 6,315 shares of Bronco Drilling CompanySEC Form 46 July 2009Common Stock, par value $0.01 · traded 1 July 2009 · filed 6 July 2009
▼ sold on the open market 5,274 shares of Bronco Drilling CompanySEC Form 46 July 2009Common Stock, par value $0.01 · traded 6 July 2009 · filed 6 July 2009
▼ sold on the open market 3,027 shares of Bronco Drilling CompanySEC Form 46 July 2009Common Stock, par value $0.01 · traded 6 July 2009 · filed 6 July 2009
▼ sold on the open market 6,492 shares of Bronco Drilling CompanySEC Form 43 June 2009Common Stock, par value $0.01 · traded 1 June 2009 · filed 3 June 2009
▼ sold on the open market 3,721 shares of Bronco Drilling CompanySEC Form 43 June 2009Common Stock, par value $0.01 · traded 1 June 2009 · filed 3 June 2009
▼ sold on the open market 23,320 shares of Bronco Drilling CompanySEC Form 43 June 2009Common Stock, par value $0.01 · traded 2 June 2009 · filed 3 June 2009
▼ sold on the open market 13,367 shares of Bronco Drilling CompanySEC Form 43 June 2009Common Stock, par value $0.01 · traded 2 June 2009 · filed 3 June 2009
acquired or disposed of, other 50,000 shares of Icx TechnologiesSEC Form 41 December 2008Common Stock, par value $0.001 · traded 26 November 2008 · filed 1 December 2008
▲ bought on the open market 101,700 shares of Bronco Drilling CompanySEC Form 410 October 2008Common Stock, par value $0.01 · traded 8 October 2008 · filed 10 October 2008
▲ bought on the open market 100,000 shares of Bronco Drilling CompanySEC Form 41 October 2008Common Stock, par value $0.01 · traded 29 September 2008 · filed 1 October 2008
▲ bought on the open market 4,095 shares of Bronco Drilling CompanySEC Form 41 October 2008Common Stock, par value $0.01 · traded 1 October 2008 · filed 1 October 2008
▲ bought on the open market 6,405 shares of Bronco Drilling CompanySEC Form 41 October 2008Common Stock, par value $0.01 · traded 1 October 2008 · filed 1 October 2008
▲ bought on the open market 476,845 shares of Javelin PharmaceuticalsSEC Form 415 May 2008Common Stock, par value $0.001 · traded 13 May 2008 · filed 15 May 2008
▲ bought on the open market 415,271 shares of Javelin PharmaceuticalsSEC Form 415 May 2008Common Stock, par value $0.001 · traded 13 May 2008 · filed 15 May 2008
converted 7,190,811 shares of Nephros (a derivative holding)SEC Form 416 November 2007Series A 10% Secured Convertible Note due 2008 · traded 14 November 2007 · filed 16 November 2007
converted an unstated number of shares of Nephros (a derivative holding)SEC Form 416 November 2007Class D Warrant for the Purchase of Shares of Common Stock · traded 14 November 2007 · filed 16 November 2007
converted 14,381,621 shares of NephrosSEC Form 416 November 2007Common Stock · traded 14 November 2007 · filed 16 November 2007
▼ sold on the open market 3,236,156 shares of Bronco Drilling CompanySEC Form 420 March 2007Common Stock, $0.01 par value · traded 16 March 2007 · filed 20 March 2007
▼ sold on the open market 270,486 shares of Bronco Drilling CompanySEC Form 46 February 2007Common Stock, $0.01 par value · traded 2 February 2007 · filed 6 February 2007
▼ sold on the open market 100,000 shares of Bronco Drilling CompanySEC Form 46 February 2007Common Stock, $0.01 par value · traded 6 February 2007 · filed 6 February 2007
▼ sold on the open market 3,400 shares of Bronco Drilling CompanySEC Form 429 January 2007Common Stock, $0.01 par value · traded 25 January 2007 · filed 29 January 2007
▼ sold on the open market 96,600 shares of Bronco Drilling CompanySEC Form 429 January 2007Common Stock, $0.01 par value · traded 26 January 2007 · filed 29 January 2007
▼ sold on the open market 120,000 shares of Bronco Drilling CompanySEC Form 429 January 2007Common Stock, $0.01 par value · traded 29 January 2007 · filed 29 January 2007
▼ sold on the open market 16,500 shares of Bronco Drilling CompanySEC Form 46 December 2006Common Stock, $0.01 par value · traded 4 December 2006 · filed 6 December 2006
▼ sold on the open market 3,600 shares of Bronco Drilling CompanySEC Form 46 December 2006Common Stock, $0.01 par value · traded 5 December 2006 · filed 6 December 2006
▼ sold on the open market 19,900 shares of Bronco Drilling CompanySEC Form 46 December 2006Common Stock, $0.01 par value · traded 6 December 2006 · filed 6 December 2006
▼ sold on the open market 2,800 shares of Bronco Drilling CompanySEC Form 43 October 2006Bronco Drilling Company, Inc. · traded 28 September 2006 · filed 3 October 2006
▼ sold on the open market 23,122 shares of Bronco Drilling CompanySEC Form 43 October 2006Bronco Drilling Company, Inc. · traded 29 September 2006 · filed 3 October 2006
▼ sold on the open market 2,800 shares of Bronco Drilling CompanySEC Form 429 September 2006Bronco Drilling Company, Inc · traded 28 September 2006 · filed 29 September 2006
▼ sold on the open market 23,122 shares of Bronco Drilling CompanySEC Form 429 September 2006Bronco Drilling Company, Inc. · traded 29 September 2006 · filed 29 September 2006
▼ sold on the open market 1,937,970 shares of Gulfport EnergySEC Form 43 May 2006Common Stock · traded 3 May 2006 · filed 3 May 2006
▼ sold on the open market 325,194 shares of Gulfport EnergySEC Form 43 May 2006Common Stock · traded 3 May 2006 · filed 3 May 2006
▼ sold on the open market 463,097 shares of Gulfport EnergySEC Form 43 May 2006Common Stock · traded 3 May 2006 · filed 3 May 2006
▼ sold on the open market 35,815 shares of Gulfport EnergySEC Form 43 May 2006Common Stock · traded 3 May 2006 · filed 3 May 2006
▼ sold on the open market 2,344,342 shares of Gulfport EnergySEC Form 43 May 2006Common Stock · traded 3 May 2006 · filed 3 May 2006
▼ sold on the open market 437,594 shares of Gulfport EnergySEC Form 43 May 2006Common Stock · traded 3 May 2006 · filed 3 May 2006
▼ sold on the open market 86,999 shares of Gulfport EnergySEC Form 43 May 2006Common Stock · traded 3 May 2006 · filed 3 May 2006
▼ sold on the open market 1,750,000 shares of Bronco Drilling CompanySEC Form 431 March 2006Common Stock, $0.01 par value · traded 29 March 2006 · filed 31 March 2006

Positions come from the unitedstates/congress-legislators roster, the Office of Government Ethics and the SEC’s Form 4 index. Every disclosed line names its own source and links the document the government published; we print what the filing says and never a price we did not read from it. Headlines and links come from the GDELT Global Knowledge Graph — the story stays with the publisher. The portrait, where we have one, is the public-domain Congressional Bioguide photograph.