Novartis AG — Director's Dealing 2016

Feb 11, 2016

SEC Form 3 — Initial Statement of Beneficial Ownership

Issuer: PROTEOSTASIS THERAPEUTICS, INC. (PTI)
CIK: 0001445283
Period of Report: 2016-02-10

Reporting Person: Novartis Bioventures Ltd (10% Owner)
Reporting Person: NOVARTIS AG (10% Owner)

Holdings (Derivative)

Security	Exercise Price	Expiration	Underlying	Shares	Ownership
Series A Convertible Redeemable Preferred Stock	$		Common Stock (1318932)		Direct
Series B Convertible Redeemable Preferred Stock	$		Common Stock (179859)		Direct

Footnotes

F1: 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.

F2: 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.

F3: 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.