Yoon Seokho Bryan Form 3 Nightstar Therapeutics / Seokho Bryan Yoon ownership change

SEC Form 3

FORM 3

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

INITIAL STATEMENT OF BENEFICIAL OWNERSHIP OF SECURITIES

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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1. Name and Address of Reporting Person^*

Yoon Seokho Bryan

(Last) (First) (Middle)

C/O NIGHTSTAR, INC.

203 CRESCENT STREET, SUITE 303

(Street)

WALTHAM MA 02453

(City) (State) (Zip)

2. Date of Event Requiring Statement (Month/Day/Year)
01/01/2019

3. Issuer Name and Ticker or Trading Symbol
Nightstar Therapeutics plc [ NITE ]

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

	Director	10% Owner
X	Officer (give title below)	Other (specify below)
General Counsel and Secretary

5. 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 Beneficially Owned
1. Title of Security (Instr. 4)	2. Amount of Securities Beneficially Owned (Instr. 4)	3. Ownership Form: Direct (D) or Indirect (I) (Instr. 5)	4. Nature of Indirect Beneficial Ownership (Instr. 5)

Table II - Derivative Securities Beneficially Owned (e.g., puts, calls, warrants, options, convertible securities)
1. Title of Derivative Security (Instr. 4)	2. Date Exercisable and Expiration Date (Month/Day/Year)		3. Title and Amount of Securities Underlying Derivative Security (Instr. 4)		4. Conversion or Exercise Price of Derivative Security	5. Ownership Form: Direct (D) or Indirect (I) (Instr. 5)	6. Nature of Indirect Beneficial Ownership (Instr. 5)
	Date Exercisable	Expiration Date	Title	Amount or Number of Shares
Stock Option (Right to Buy)	(1)	11/05/2027	Ordinary Shares(2)	160,000	22.78	D
Stock Option (Right to Buy)	(3)	01/30/2028	Ordinary Shares(2)	15,000	14.24	D

Explanation of Responses:

1. 43,333 shares vested as of January 1, 2019. The remainder of the underlying shares shall vest on a pro rata monthly basis through November 1, 2021.

2. The ordinary shares, nominal value GBP 0.01 per share, of the Issuer may be represented by American Depositary Shares ("ADSs"). Each ADS represents one ordinary share of the Issuer.

3. 25% vested as of January 1, 2019. The remainder of the underlying shares will vest in in 36 equal monthly installments thereafter.

Remarks:

Exhibit List: Exhibit 24.1 - Power of Attorney

	/s/ Seokho Bryan Yoon	01/02/2019
	** 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 5 (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).
Note: File three copies of this Form, one of which must be manually signed. If space is insufficient, see Instruction 6 for procedure.
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