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 *
HARTGRING CORNELIS
   2. Issuer Name and Ticker or Trading Symbol
PDF SOLUTIONS INC [PDFS] 		5. Relationship of Reporting Person(s) to Issuer
(Check all applicable)
_____ Director _____ 10% Owner
__X__ Officer (give title below) _____ Other (specify below)
Vice President, CSS
(Last)
(First)
(Middle)
333 W. SAN CARLOS ST., SUITE 1000		 3. Date of Earliest Transaction (Month/Day/Year)
05/28/2013
(Street)

SAN JOSE, CA 95110		 4. If Amendment, Date Original Filed(Month/Day/Year)
 6. Individual or Joint/Group Filing(Check Applicable Line)
_X_ Form filed by One Reporting Person
___ 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 05/28/2013   A   13,915 (1) A $ 0 36,403 D  
Common Stock 05/28/2013   F(2)   654 D $ 18.59 35,749 D  

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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
HARTGRING CORNELIS
333 W. SAN CARLOS ST.
SUITE 1000
SAN JOSE, CA 95110		       Vice President, CSS  

Signatures

 /s/ Gregory Walker, Attorney-in-Fact for Cornelis Hartgring   05/30/2013
**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) These shares represent an award of restricted stock units. Of the total shares, (1) 6,957 shares of restricted stock units shall vest as follows: 25% of the Total Shares vested on the May 28, 2013 and 25% of the Total Shares shall vest annually thereafter until fully vested, subject to the Recipient's continued Service through each applicable vesting date; and (2) 6,958 shares of restricted stock units shall vest as follows: 12.5% of the Total Shares vested on the date that is six (6) month after May 1, 2013 and 12.5% of the Total Shares shall vest on each date that is six (6) months thereafter until fully vested, subject to the Recipient's continued Service through each applicable vesting date.
(2) This represents a disposition of shares to the Company to satisfy tax withholding obligations with respect to the vesting of restricted Stock rights. This is not a sale of shares in the market.

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