Ownership Submission
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, 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 *
  Novartis Bioventures Ltd
 2. Date of Event Requiring Statement (Month/Day/Year)
02/10/2016		 3. Issuer Name and Ticker or Trading Symbol
PROTEOSTASIS THERAPEUTICS, INC. [PTI]
(Last)
(First)
(Middle)
131 FRONT STREET		 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 Original Filed(Month/Day/Year)
(Street)

HAMILTON, D0 HM12		 6. Individual or Joint/Group Filing(Check Applicable Line)
___ Form filed by One Reporting Person
_X_ Form filed by More than One Reporting Person
(City)
(State)
(Zip)
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)

Reminder: Report on a separate line for each class of securities beneficially owned directly or indirectly. SEC 1473 (7-02)
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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 of Derivative Security: 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 A Convertible Redeemable Preferred Stock   (1)   (1) Common Stock 1,318,932 (1) $ (1) D (2)  
Series B Convertible Redeemable Preferred Stock   (3)   (3) Common Stock 179,859 (3) $ (3) D (2)  

Reporting Owners

Reporting Owner Name / Address Relationships
Director 10% Owner Officer Other
Novartis Bioventures Ltd
131 FRONT STREET
HAMILTON, D0 HM12		     X    
NOVARTIS AG
LICHTSTRASSE 35
CH-4056 BASEL, V8 		     X    

Signatures

/s/ Simon Zivi, Chairman 02/10/2016
**Signature of Reporting Person Date
/s/ Laurieann Chaikowsky, Authorized Signatory 02/10/2016
**Signature of Reporting Person Date

Explanation of Responses:

* 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).
(1) The Series A Convertible Redeemable Preferred Stock (the "Series A Shares") are convertible on a 10.8102-to-1 basis into the Issuer's Common Stock at any time at the election of the Reporting Person and will automatically convert, together with the accrued but unpaid dividends, upon the closing of the Issuer's initial public offering into the number of shares of the Issuer's Common Stock shown in column 3. The Series A Shares do not have an expiration date.
(2) These securities are held directly by Novartis Bioventures Ltd. ("Novartis Bioventures"). Novartis Bioventures is a corporation organized under the laws of Bermuda and is an indirect wholly-owned subsidiary of Novartis AG. Novartis AG is a corporation organized under the laws of Switzerland and is the publicly owned parent of Novartis Bioventures Ltd.
(3) The Series B Convertible Redeemable Preferred Stock (the "Series B Shares") are convertible on a 10.8102-to-1 basis into the number of shares of the Issuer's Common Stock as shown in column 3 at any time at the election of the Reporting Person and will automatically convert upon the closing of the Issuer's initial public offering. The Series B Shares do not have an expiration date.

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