Ownership Submission
FORM 4
Check this box if no longer subject to Section 16. Form 4 or Form 5 obligations may continue. See Instruction 1(b).
UNITED STATES SECURITIES AND EXCHANGE COMMISSION
Washington, D.C. 20549

STATEMENT OF CHANGES IN BENEFICIAL OWNERSHIP OF SECURITIES

Filed pursuant to Section 16(a) of the Securities Exchange Act of 1934, Section 17(a) of the Public Utility Holding Company Act of 1935 or Section 30(h) of the Investment Company Act of 1940
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(Print or Type Responses)
1. Name and Address of Reporting Person *
Lambda Investors LLC
  2. Issuer Name and Ticker or Trading Symbol
NEPHROS INC [NEPH]
5. Relationship of Reporting Person(s) to Issuer
(Check all applicable)
_____ Director __X__ 10% Owner
_____ Officer (give title below) _____ Other (specify below)
(Last)
(First)
(Middle)
411 WEST PUTNAM AVENUE, SUITE 125
3. Date of Earliest Transaction (Month/Day/Year)
05/23/2013
(Street)

GREENWICH, CT 06830
4. If Amendment, Date Original Filed(Month/Day/Year)
6. Individual or Joint/Group Filing(Check Applicable Line)
___ Form filed by One Reporting Person
_X_ Form filed by More than One Reporting Person
(City)
(State)
(Zip)
Table I - Non-Derivative Securities Acquired, Disposed of, or Beneficially Owned
1.Title of Security
(Instr. 3)
2. Transaction Date (Month/Day/Year) 2A. Deemed Execution Date, if any (Month/Day/Year) 3. Transaction Code
(Instr. 8)
4. Securities Acquired (A) or Disposed of (D)
(Instr. 3, 4 and 5)
5. Amount of Securities Beneficially Owned Following Reported Transaction(s)
(Instr. 3 and 4)
6. Ownership Form: Direct (D) or Indirect (I)
(Instr. 4)
7. Nature of Indirect Beneficial Ownership
(Instr. 4)
Code V Amount (A) or (D) Price
Common Stock, par value $0.001 05/23/2013   P   2,992,884 A (1) 6,721,676 I Held directly by Lambda Investors LLC (1) (2) (3)

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Table II - Derivative Securities Acquired, Disposed of, or Beneficially Owned
(e.g., puts, calls, warrants, options, convertible securities)
1. Title of Derivative Security
(Instr. 3)
2. Conversion or Exercise Price of Derivative Security 3. Transaction Date (Month/Day/Year) 3A. Deemed Execution Date, if any (Month/Day/Year) 4. Transaction Code
(Instr. 8)
5. Number of Derivative Securities Acquired (A) or Disposed of (D)
(Instr. 3, 4, and 5)
6. Date Exercisable and Expiration Date
(Month/Day/Year)
7. Title and Amount of Underlying Securities
(Instr. 3 and 4)
8. Price of Derivative Security
(Instr. 5)
9. Number of Derivative Securities Beneficially Owned Following Reported Transaction(s)
(Instr. 4)
10. Ownership Form of Derivative Security: Direct (D) or Indirect (I)
(Instr. 4)
11. Nature of Indirect Beneficial Ownership
(Instr. 4)
Code V (A) (D) Date Exercisable Expiration Date Title Amount or Number of Shares

Reporting Owners

Reporting Owner Name / Address Relationships
 Director  10% Owner  Officer  Other
Lambda Investors LLC
411 WEST PUTNAM AVENUE
SUITE 125
GREENWICH, CT 06830
    X    
WEXFORD CAPITAL LP
411 WEST PUTNAM AVENUE
SUITE 125
GREENWICH, CT 06830
    X    
Wexford GP LLC
C/O WEXFORD CAPITAL LP
SUITE 125
GREENWICH, CT 06830
    X    
DAVIDSON CHARLES E
C/O WEXFORD CAPITAL LP
411 WEST PUTNAM AVE.
GREENWICH, CT 06830
    X    
JACOBS JOSEPH
C/O WEXFORD CAPITAL LP
411 WEST PUTNAM AVENUE, SUITE 125
GREENWICH, CT 06830
    X    

Signatures

 Lambda Investors LLC By: Arthur Amron, Vice President and Assistant Secretary   06/04/2013
**Signature of Reporting Person Date

 Wexford Capital LP, By: Wexford GP LLC, its general partner By Arthur Amron, Vice President and Assistant Secretary   06/04/2013
**Signature of Reporting Person Date

 Wexford GP LLC, By Arthur Amron, Vice Presidentand Assistant Secretary   06/04/2013
**Signature of Reporting Person Date

 Charles E. Davidson   06/04/2013
**Signature of Reporting Person Date

 Joseph M. Jacobs   06/04/2013
**Signature of Reporting Person Date

Explanation of Responses:

* If the form is filed by more than one reporting person, see Instruction 4(b)(v).
** Intentional misstatements or omissions of facts constitute Federal Criminal Violations. See 18 U.S.C. 1001 and 15 U.S.C. 78ff(a).
(1) On May 23, 2013, Lambda Investors LLC ('Lambda") purchased, pursuant to a rights offering with Nephros, Inc., 2,992,884 shares of Common Stock at a purchase price of $0.60 per share for a cost of $1,795,730.40.
(2) This form is jointly filed by Lambda, Wexford Capital LP ("Wexford"), Charles E. Davidson ("Davidson"), Joseph M. Jacobs ("Jacobs") and Wexford GP LLC ("Wexford GP"). The reported securities are held directly by Lambda and by Wexford. Wexford serves as manager, investment advisor or sub-advisor of Lambda, and as such may be deemed to share beneficial ownership of the securities beneficially owned by Lambda, but disclaims such beneficial ownership to the extent such beneficial ownership exceeds its pecuniary interest. Wexford GP, as the general partner of Wexford, may be deemed to share beneficial ownership of the securities beneficially owned by Lambda, but disclaims such ownership to the extent such beneficial ownership exceeds its pecuniary interest. (continued under Footnote (3) below).
(3) (continued from Footnote (2) above) Messrs. Davidson and Jacobs, as the controlling persons of Wexford GP, may be deemed to share beneficial ownership of any securities beneficially owned by Lambda for which Wexford serves as manager, investment advisor or sub-advisor, but disclaim such beneficial ownership to the extent such beneficial ownership exceeds their pecuniary interest.

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