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 *
Magstadt Brian J
  2. Issuer Name and Ticker or Trading Symbol
SIMPSON MANUFACTURING CO INC /CA/ [SSD]
5. Relationship of Reporting Person(s) to Issuer
(Check all applicable)
_____ Director _____ 10% Owner
__X__ Officer (give title below) _____ Other (specify below)
Chief Financial Officer
(Last)
(First)
(Middle)
5956 W. LAS POSITAS BLVD.
3. Date of Earliest Transaction (Month/Day/Year)
02/15/2018
(Street)

PLEASANTON, CA 94588
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
Performance stock units 02/15/2018   A   5,017 A $ 0 5,017 (1) D  
Common Stock (RSUs awarded February 4, 2017)               6,372 (2) D  
Common Stock (PSUs awarded February 4, 2017)               12,763 (3) D  
Common Stock (RSUs awarded February 1, 2016)               7,104 (4) D  
Common Stock (PSUs awarded February 1, 2016)               8,750 (5) D  
Common Stock (RSUs awarded February 2, 2015)               5,313 (6) D  
Common Stock (RSUs awarded February 3, 2014)               5,681 (7) D  
Common Stock (RSUs awarded February 6, 2013)               3,281 (8) D  
Common Stock (RSUs awarded January 30, 2012)               1,450 D  
Common Stock               1,008 D  
Common Stock               398 I (9) By Trust

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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
Restricted stock units (10) $ 0 02/15/2018   A   1,912     (10)   (10) Common Stock 1,912 $ 0 1,912 D  

Reporting Owners

Reporting Owner Name / Address Relationships
 Director  10% Owner  Officer  Other
Magstadt Brian J
5956 W. LAS POSITAS BLVD.
PLEASANTON, CA 94588
      Chief Financial Officer  

Signatures

 /s/BRIAN J. MAGSTADT   02/20/2018
**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) Amount of performance stock units (PSUs) awarded on February 15, 2018. PSUs vest fully on February 15, 2021, subject to the Company's performance on revenue growth (50%) and return on invested capital (50%). The number of PSU's presented assumes the number of shares vested based on meeting targeted performance goals and net of the number of shares expected to be withheld to cover the estimated income taxes due on vesting.
(2) Amount includes 6,372 shares of restricted stock units (RSUs) awarded on February 4, 2017. RSUs vest one fourth on February 15, 2017, February 15, 2018, February 15, 2019, and February 15, 2020. The 6,372 shares are net of the number of shares expected to be withheld to cover the estimated income taxes due on vesting.
(3) Amount includes 12,763 shares of restricted stock units (RSUs) awarded on February 4, 2017. RSUs vest fully on February 15, 2020, subject to the Company's performance on revenue growth (50%) and return on invested capital (50%). The 12,763 shares assume that the number of shares that vest are based on targeted performance and are net of the number of shares expected to be withheld to cover the estimated income taxes due on vesting.
(4) Amount includes 7,104 shares of restricted stock units (RSUs) awarded on February 1, 2016. RSUs vest one fourth on each of the award date and the first, second and third anniversaries of the award date. The 7,104 shares are net of the number of shares expected to be withheld to cover the estimated income taxes due on vesting.
(5) Amount includes 8,750 shares of restricted stock units (RSUs) awarded on February 1, 2016. RSUs vest fully on the third anniversary of the award date subject to the Company's relative performance versus the S&P Smallcap 600 Index. The 8,750 shares assume that the maximum number of shares will vest, based on performance at the highest level, and are net of the number of shares expected to be withheld to cover the estimated income taxes due on vesting.
(6) Amount includes 5,313 shares of restricted stock units (RSUs) awarded on February 2, 2015. RSUs vest three fourths on the third anniversary of the award date and one fourth on the fourth anniversary of the award date. The 5,313 shares are net of the number of shares expected to be withheld to cover the estimated income taxes due on vesting.
(7) Amount includes 5,681 shares of restricted stock units (RSUs) awarded on February 3, 2014. RSUs vest three fourths on the third anniversary of the award date and one fourth on the fourth anniversary of the award date. The 5,681 shares are net of the number of shares expected to be withheld to cover the estimated income taxes due on vesting.
(8) Amount includes 3,281 shares of restricted stock units (RSUs) awarded on February 6, 2013. RSUs vest three fourths on the third anniversary of the award date and one fourth on the fourth anniversary of the award date. The 3,281 shares are net of the number of shares expected to be withheld to cover the estimated income taxes due on vesting.
(9) The shares are owned by the Simpson Manuafacturing Co., Inc. Profit Sharing Plan for Salaried Employees (the "Plan") of which the reporting person is a participant. The Plan qualifies under sections 401(a)(26) and 410 of the Internal Revenue Code.
(10) Amount includes 1,912 shares of restricted stock units (RSUs) awarded on February 15, 2018. Twenty percent of RSUs vest on February 15, 2019, forty percent on February 17, 2020 and February 15, 2021. Granted RSUs do not have exercise dates or an expiration date.

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