ECOLAB INC. — Director's Dealing 2011

Aug 26, 2011

SEC Form 4 — Statement of Changes in Beneficial Ownership

Issuer: ECOLAB INC (ECL)
CIK: 0000031462
Period of Report: 2011-08-23

Reporting Person: GATES WILLIAM H III (10% Owner, See Footnotes 1,2)
Reporting Person: CASCADE INVESTMENT LLC (See Remarks)

Non-Derivative Transactions

Date	Security	Code	Shares	Price	A/D	Holdings After	Ownership
2011-08-23	Common Stock	P	930162.0000	$48.8192	Acquired	19759748.0000	Indirect
2011-08-23	Common Stock	P	472290.0000	$48.4935	Acquired	20232038.0000	Indirect
2011-08-23	Common Stock	P	381034.0000	$47.4572	Acquired	20613072.0000	Indirect

Footnotes

F1: This transaction was executed in multiple trades at prices ranging from $48.65 to $49.00. The reporting person hereby undertakes to provide upon request to the SEC staff, the issuer or a security holder of the issuer full information regarding the number of shares and prices at which the transactions were effected.

F2: Mr. Gates may be deemed to be the beneficial owner of more than 10% of Ecolab Inc.'s common stock for purposes of Section 13(d) of the Securities Exchange Act of 1934 (the "Act") and therefore subject to Section 16 of the Act. For purposes of Rule 16a-1(a)(2) under the Act, however, Mr. Gates is the beneficial owner of only the securities held by Cascade Investment, L.L.C. and Mr. Gates disclaims beneficial ownership of any Ecolab Inc. common stock held by any other person. Both reporting persons disclaim membership in a "group" with one another or with any other person as that term is used in Section 13(d) of the Act, and the filing of this Form 4 shall not be deemed an admission that either reporting person is a member of such a group.

F3: This transaction was executed in multiple trades at prices ranging from $47.65 to $48.645. The reporting person hereby undertakes to provide upon request to the SEC staff, the issuer or a security holder of the issuer full information regarding the number of shares and prices at which the transactions were effected.

F4: This transaction was executed in multiple trades at prices ranging from $46.65 to $47.645. The reporting person hereby undertakes to provide upon request to the SEC staff, the issuer or a security holder of the issuer full information regarding the number of shares and prices at which the transactions were effected.