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* Hadley Harbor Master Investors (Cayman) L.P. (Last) (First) (Middle) C/O WELLINGTON MANAGEMENT COMPANY LLP 280 CONGRESS STREET (Street) BOSTON MA 02210 (City) (State) (Zip)	2. Date of Event Requiring Statement (Month/Day/Year) 07/19/2017	3. Issuer Name and Ticker or Trading Symbol Kala Pharmaceuticals, Inc. [ KALA ]
		4. Relationship of Reporting Person(s) to Issuer (Check all applicable) Director X 10% Owner Officer (give title below) Other (specify below)	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
Series B-1 Convertible Preferred Stock	(1)	(1)	Common Stock	888,894	(1)	D
Series C Convertible Preferred Stock	(2)	(2)	Common Stock	846,566	(2)	D

Explanation of Responses:

1. The Series B-1 Convertible Preferred Stock is convertible into Common Stock on a 5.2083-for-one basis into the number of shares of Common Stock shown in column 3 at any time at the holder's election and automatically upon the closing of the Issuer's initial public offering. The shares have no expiration date.

2. The Series C Convertible Preferred Stock is convertible into Common Stock on a 5.2083-for-one basis into the number of shares of Common Stock shown in column 3 at any time at the holder's election and automatically upon the closing of the Issuer's initial public offering. The shares have no expiration date.

	Hadley Harbor Master Investors (Cayman) L.P. By: Wellington Alternative Investments LLC, as General Partner, /s/Matthew N. Shea, Title: Authorized Person	07/19/2017
	** 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 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).
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