W.R. Grace & Co. (GRA) 10-Q 2012 Q2 Quarterly report

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Exhibit 15

August 6, 2012

Securities and Exchange Commission
100 F Street, N.E.
Washington, D.C. 20549

Commissioners:

        We are aware that our report dated August 6, 2012 on our review of interim financial information of W. R. Grace & Co. (the "Company") for the three-month and six-month periods ended June 30, 2012 and June 30, 2011 and included in the Company's Quarterly Report on Form 10-Q for the quarter ended June 30, 2012, is incorporated by reference in its Registration Statements on Form S-8 dated May 12, 2000 and April 28, 2011.

Very truly yours,

/s/PRICEWATERHOUSECOOPERS LLP
McLean, Virginia

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Exhibit 15