Aquinox Pharmaceuticals Inc (AQXP): Baker Bros. Advisors Pushes Stake to Over 45%

Page 3 of 9 – SEC Filing

CUSIP No.   03842B101

Page   3   of   9   Pages

1.	NAMES OF REPORTING PERSONS Baker Bros. Advisors (GP) LLC
2.	CHECK THE APPROPRIATE BOX IF A MEMBER OF A GROUP* (a) ¨ (b) ¨
3.	SEC USE ONLY
4.	SOURCE OF FUNDS* OO
5.	CHECK BOX IF DISCLOSURE OF LEGAL PROCEEDINGS IS REQUIRED PURSUANT TO ITEM 2(d) or 2(e)   o
6.	CITIZENSHIP OR PLACE OF ORGANIZATION Delaware
NUMBER OF SHARES BENEFICIALLY OWNED BY EACH REPORTING PERSON WITH		7.	SOLE VOTING POWER 10,536,092
		8.	SHARED VOTING POWER: 0
		9.	SOLE DISPOSITIVE POWER: 10,536,092
		10.	SHARED DISPOSITIVE POWER: 0
11.	AGGREGATE AMOUNT BENEFICIALLY OWNED BY EACH REPORTING PERSON: 10,536,092
12.	CHECK BOX IF THE AGGREGATE AMOUNT IN ROW (11) EXCLUDES CERTAIN SHARES (See Instructions) ¨
13.	PERCENT OF CLASS REPRESENTED BY AMOUNT IN ROW (11) 45.1%(1)
14.	TYPE OF REPORTING PERSON (See Instructions) HC, OO

(1)

Based on 23,365,137 shares of common stock that will be outstanding following the offering described in the Issuer’s Prospectus filed with the SEC on September 20, 2016.