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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1. Name and Address of Reporting Person *   Watchorn Derek John 2. Date of Event Requiring Statement (Month/Day/Year) 04/26/2011 3. Issuer Name and Ticker or Trading Symbol PATHEON INC [PTI] (Last) (First) (Middle) 16530 CONCESSION 8, RR1 4. Relationship of Reporting Person(s) to Issuer (Check all applicable) __X__ Director _____ 10% Owner _____ Officer (give title below) _____ Other (specify below) 5. If Amendment, Date Original Filed(Month/Day/Year) (Street) SCHOMBERG, A6 L0G 1T0 6. Individual or Joint/Group Filing(Check Applicable Line) _X_ Form filed by One Reporting Person ___ 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) Restricted Voting Shares 30,825 D Â

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
Deferred Share Units	  (1)	  (1)	Restricted Voting Shares	101,376	$ (1)	D	Â
Employee Stock Option (right to buy)	01/22/2007	01/22/2012	Restricted Voting Shares	5,000	$ 7.64 (2)	D	Â
Employee Stock Option (right to buy)	03/28/2008	03/28/2013	Restricted Voting Shares	5,000	$ 9 (3)	D	Â
Employee Stock Option (right to buy)	04/21/2008	04/21/2014	Restricted Voting Shares	5,000	$ 8.12 (4)	D	Â
Employee Stock Option (right to buy)	06/09/2010	06/09/2015	Restricted Voting Shares	5,000	$ 7.51 (5)	D	Â

Reporting Owners

Reporting Owner Name / Address	Relationships
	Director	10% Owner	Officer	Other
Watchorn Derek John 16530 CONCESSION 8 RR1 SCHOMBERG, A6 L0G 1T0	  X	Â	Â	Â

Signatures

/s/ David S Field, Attorney-in-fact		04/26/2011
**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)	Each deferred share unit entitles its holder, upon ceasing to be a director, to receive an amount of cash having the same value as one restricted voting share of Patheon Inc. at such time.
(2)	The exercise price was converted from C$12.28 using the noon rate of exchange of the Bank of Canada on the date of grant. The actual exercise price will be the Canadian dollar amount regardless of the exchange rate on the date of grant or of exercise.
(3)	The exercise price was converted from C$13.21 using the noon rate of exchange of the Bank of Canada on the date of grant. The actual exercise price will be the Canadian dollar amount regardless of the exchange rate on the date of grant or of exercise.
(4)	The exercise price was converted from C$11.04 using the noon rate of exchange of the Bank of Canada on the date of grant. The actual exercise price will be the Canadian dollar amount regardless of the exchange rate on the date of grant or of exercise.
(5)	The exercise price was converted from C$9.43 using the noon rate of exchange of the Bank of Canada on the date of grant. The actual exercise price will be the Canadian dollar amount regardless of the exchange rate on the date of grant or of exercise.
  Remarks: Exhibit List Exhibit 24 - Power of Attorney

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