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 *   LAGESON ANGELA D 2. Date of Event Requiring Statement (Month/Day/Year) 02/23/2010 3. Issuer Name and Ticker or Trading Symbol PENTAIR INC [PNR] (Last) (First) (Middle) 5500 WAYZATA BLVD., SUITE 800 4. Relationship of Reporting Person(s) to Issuer (Check all applicable) _____ Director _____ 10% Owner __X__ Officer (give title below) _____ Other (specify below) Sr. Vice President, Secretary 5. If Amendment, Date Original Filed(Month/Day/Year) (Street) GOLDEN VALLEY, MN 55416 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) Common Stock 4,451.898 (1) D   Common Stock - ESOP 657.0985 I By ESOP Common Stock - Restricted Stock Units 1,986 (2) 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
Employee Stock Option (right to buy)	03/01/2006(3)	03/01/2015	Common Stock	7,863 (4)	$ 41.12	D	Â
Employee Stock Option (right to buy)	03/01/2007(3)	03/01/2016	Common Stock	5,793 (4)	$ 41.17	D	Â
Employee Stock Option (right to buy)	03/01/2008(3)	03/01/2017	Common Stock	6,431 (4)	$ 31.56	D	Â
Employee Stock Option (right to buy)	03/03/2009(3)	03/03/2018	Common Stock	5,597 (4)	$ 32.4	D	Â
Employee Stock Option (right to buy)	03/03/2010(3)	03/03/2019	Common Stock	9,629 (5)	$ 19.13	D	Â

Reporting Owners

Reporting Owner Name / Address	Relationships
	Director	10% Owner	Officer	Other
LAGESON ANGELA D 5500 WAYZATA BLVD. SUITE 800 GOLDEN VALLEY, MN 55416	Â	Â	  Sr. Vice President, Secretary	Â

Signatures

s/ Angela D. Lageson		03/01/2010
**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)	Amount of securities beneficially owned includes 4,399 restricted shares that remain subject to a vesting condition; and 52.898 shares acquired under a dividend reinvestment plan.
(2)	Restricted stock units granted pursuant to and subject to a vesting condition of the Pentair, Inc. 2008 Omnibus Stock Incentive Plan, as Amended. Each restricted stock unit represents a right to receive one share of Pentair, Inc. common stock upon vesting.
(3)	One-third of the stock options become exercisable on the first, second, and third anniversary of the grant.
(4)	Employee stock option granted under the Pentair, Inc. Omnibus Stock Incentive Plan.
(5)	Employee stock option granted under the Pentair, Inc. 2008 Omnibus Stock Incentive Plan, as Amended.

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