Richard A Lemmon Form 4 TETRA TECH / RICHARD A LEMMON ownership change

SEC Form 4

FORM 4

UNITED STATES SECURITIES AND EXCHANGE COMMISSION
Washington, D.C. 20549

STATEMENT OF CHANGES IN BENEFICIAL OWNERSHIP

Filed pursuant to Section 16(a) of the Securities Exchange Act of 1934
or Section 30(h) of the Investment Company Act of 1940

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Check this box if no longer subject to Section 16. Form 4 or Form 5 obligations may continue. See Instruction 1(b).

1. Name and Address of Reporting Person^*

LEMMON RICHARD A

(Last) (First) (Middle)

3475 EAST FOOTHILL BOULEVARD

(Street)

PASADENA, CA 91107

(City) (State) (Zip)

2. Issuer Name and Ticker or Trading Symbol
TETRA TECH INC [ TTEK ]

5. Relationship of Reporting Person(s) to Issuer
(Check all applicable)

	Director	10% Owner
X	Officer (give title below)	Other (specify below)
SVP, CORPORATE ADMINISTRATION

3. Date of Earliest Transaction (Month/Day/Year)
11/21/2017

4. If Amendment, Date of 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

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	11/21/2017		A		6,156(1)	A	$0	36,002	D
COMMON STOCK	11/21/2017		A		5,817(2)	A	$0	41,819	D
COMMON STOCK	11/21/2017		F		4,533(3)	D	$50	37,286	D
COMMON STOCK	11/21/2017		F		402(4)	D	$50	36,884	D

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 Securities Underlying Derivative Security (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: 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

Explanation of Responses:

1. Each performance share unit ("PSU") represents the right to receive one share of Common Stock. The PSUs awarded cliff-vest after a 3-year performance period. The Performance Period was the Company's fiscal years 2015, 2016 and 2017. The number of PSUs earned by the Awardee was determined at the end of the Performance Period by measuring earnings per share ("EPS") growth, which was 35% year-over-year growth. Therefore, 200% of the 3,078 PSUs awarded on November 21, 2014 were earned and vested on November 21, 2017.

2. Each performance share unit ("PSU") represents the right to receive one share of Common Stock. The PSUs awarded cliff-vest after a 3-year performance period. The Performance Period was the Company's fiscal years 2015, 2016 and 2017. The number of PSUs earned by the Awardee for the Performance Period was determined at the end of the Performance Period by measuring relative total shareholder return ("TSR"), with equal weight given to the selected industry peer group and to the S&P 1000. The TSR peer group performance percentile was 89%, and the TSR S&P 1000 performance percentile was 82%. Straight line interpolation determined the vesting credit percentage. Therefore, 189% of the 3,078 PSUs awarded on November 21, 2014 were earned and vested on November 21, 2017.

3. 4,533 of the shares underlying PSUs which vested on 11/21/2017 were withheld to pay the related tax liability.

4. 402 of the shares underlying restricted stock which vested on 11/21/2017 were withheld to pay the related tax liability.

Remarks:

	Janis B. Salin for Richard A. Lemmon	11/22/2017
	** Signature of Reporting Person	Date
Reminder: Report on a separate line for each class of securities beneficially owned directly or indirectly.
* 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).
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