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
OMB APPROVAL
OMB Number: 3235-0287
Expires: January 31, 2005
Estimated average burden hours per response... 0.5

(Print or Type Responses)
1. Name and Address of Reporting Person *
WATTS GERARD J
  2. Issuer Name and Ticker or Trading Symbol
CYANOTECH CORP [CYAN]
5. Relationship of Reporting Person(s) to Issuer
(Check all applicable)
_____ Director _____ 10% Owner
__X__ Officer (give title below) _____ Other (specify below)
COO
(Last)
(First)
(Middle)
73-4460 QUEEN KAAHUMANU HWY #102
3. Date of Earliest Transaction (Month/Day/Year)
04/05/2018
(Street)

KAILUA-KONA, HI 96740
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
Cyanotech common stock 04/05/2018   M   57 A $ 0 57 D  
Cyanotech common stock 04/05/2018   F(1)   22 D $ 5.25 35 D  

Reminder: Report on a separate line for each class of securities beneficially owned directly or indirectly.
Persons who respond to the collection of information contained in this form are not required to respond unless the form displays a currently valid OMB control number. SEC 1474 (9-02)

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
Cyanotech common stock options $ 4.72               (2) 08/18/2024 Cyanotech common stock 45,000   45,000 D  
Restricted stock units (3) 04/05/2018   M     57   (4)   (4) Cyanotech common stock 57 $ 0 113 D  

Reporting Owners

Reporting Owner Name / Address Relationships
 Director  10% Owner  Officer  Other
WATTS GERARD J
73-4460 QUEEN KAAHUMANU HWY #102
KAILUA-KONA, HI 96740
      COO  

Signatures

 /s/ Dan Sprague, by Power of Attorney   04/09/2018
**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) The reporting person is reporting the withholding by the Issuer of 22 shares of common stock that vested on April 5, 2018 pursuant to the April 5, 2017 RSU grant, but that were not issued in order to satisfy the reporting person's tax withholding obligations in connection with the delivery of the converted common stock to the reporting person as of April 6, 2018.
(2) Mr Watts acquired 45,000 stock options on 8/18/2014, of which 15,000 options became exercisable on 8/18/2015, 15,000 options became exercisable on 8/18/2016, and 15,000 options became exercisable on 8/18/2016.
(3) Each restricted stock unit represents the contingent right to receive one (1) share of Cyanotech common stock.
(4) The restricted stock units shall vest as to 57 shares on 4/5/2019 and 56 shares on 4/5/2020, in each case subject to continued service with Cyanotech on the vesting date.

Note: File three copies of this Form, one of which must be manually signed. If space is insufficient, see Instruction 6 for procedure.

Potential persons who are to respond to the collection of information contained in this form are not required to respond unless the form displays a currently valid OMB number.