ECOLAB INC. — Director's Dealing 2011

May 21, 2011

SEC Form 4 — Statement of Changes in Beneficial Ownership

Issuer: ECOLAB INC (ECL)
CIK: 0000031462
Period of Report: 2011-05-20

Reporting Person: NESTEGARD SUSAN K (President, Global Healthcare)

Non-Derivative Transactions

Date	Security	Code	Shares	Price	A/D	Holdings After	Ownership
2011-05-20	Common Stock	M	40000	$24.5525	Acquired	40000	Direct
2011-05-20	Common Stock	F	26263	$52.30	Disposed	13737	Direct

Derivative Transactions

Date	Security	Exercise Price	Code	Shares	A/D	Expiration	Underlying	Ownership
2011-05-20	Employee Stock Option (Right to Buy)	$24.5525	M	40000	Disposed	2013-03-03	Common Stock (40000)	Direct

Holdings (Non-Derivative)

Security	Shares	Ownership
Common Stock	854.903	Indirect

Footnotes

F1: Reflects the reporting person's payment of the exercise price and withholding taxes for a stock option issued in accordance with Rule 16b-3 by withholding shares of Ecolab Common Stock.

F2: Number of UNITS in the Ecolab Stock Fund of the Ecolab Savings Plan (401(k) Plan) as of March 31, 2011. Includes 2.987 UNITS acquired since the reporting person's last report. (The 854.903 UNITS are the equivalent of approximtely 1,594 shares of the issuer's Common Stock.)

F3: Option granted under the Ecolab Inc. 2002 Stock Incentive Plan. The option became exercisable, on a cumulative basis, as to one-third of the option shares (excluding any fractional portion less than one share), on each of the first and second anniversaries of the date of grant and as to the remaining shares on the third anniversary of the date of grant. The option was originally reported as a grant of 20,000 shares at a price of $49.105 per share, and was adjusted following the company's two-for-one stock split paid June 6, 2003.