ROH Rohm & Haas

Rohm and Haas Company, a Delaware corporation (the “Company”), supplements and amends its Registration Statement on Form 8-A, dated October 26, 2000 (as amended on July 14, 2008, the “Registration Statement”) as follows:

Item 1. Description of Securities to be Registered.

Reference is hereby made to the Preferred Stock Rights Agreement by and between the Company and Computershare Trust Company, N.A. (formerly known as EquiServe Trust Company, N.A.), as rights agent (the “Rights Agent”), dated as of October 26, 2000 and amended as of July 9, 2008 (the “Rights Agreement”).

On March 9, 2009, The Dow Chemical Company (“Dow”), certain trusts for the benefit of charitable beneficiaries and certain Haas family members (the “Haas Trusts”) and Paulson & Co., Inc., on behalf of the several funds and accounts managed by it (together with the Haas Trusts, the “Investors”) entered into an Investment Agreement pursuant to which the Investors agreed to make certain equity investments in Dow pursuant to the terms of the Investment Agreement.

In contemplation of the execution of the Investment Agreement, on March 9, 2009, the Company entered into a Second Amendment (the “Second Amendment”) to the Rights Agreement for the purpose of amending the Rights Agreement to render it inapplicable to the Investment Agreement and the transactions contemplated thereby. In particular, the Second Amendment provides that no person will be deemed to be an Acquiring Person (as defined in the Rights Agreement) and no distribution of rights will occur solely by virtue of the approval, execution, delivery, adoption or performance of the Investment Agreement or the consummation transactions contemplated thereby or the public announcement of any of the forgoing.

The Second Amendment is attached as Exhibit 4.3 hereto and is incorporated herein by reference.

Item 2. Exhibits.