Riverbed Technology (RVBD)

Explanatory Note

This Amendment No. 1 on Form 10-Q/A (“Amendment No. 1”) to the Company’s Quarterly Report on Form 10-Q for the quarterly period ended March 31, 2009 (“Quarterly Report”), initially filed with the Securities and Exchange Commission on April 30, 2009, is being filed solely to correct an error in the table in Footnote 8, Deferred Revenue, of Part 1, Item 1 of the Quarterly Report. Deferred product revenue as of March 31, 2009 is lower by $7,673,000, and deferred support and services revenue as of March 31, 2009 is higher by $7,673,000, than the respective amounts originally filed in our Quarterly Report. The total reported current and non-current deferred revenue amounts in our Quarterly Report are correct, and there are no changes to the amounts shown in our condensed consolidated balance sheets.

No other changes in our Quarterly Report are being made by this Amendment No. 1. However, in accordance with Rule 12b-15 promulgated under the Securities Exchange Act of 1934, as amended, the complete text of Part I, Item 1, as amended, is included herein.

This Amendment No. 1 also amends and restates the exhibit list and refiles certain exhibits specified herein, including currently dated certifications of our chief executive officer and chief financial officer set forth as Exhibits 31.1, 31.2 and 32.1 hereto. This Amendment No. 1 speaks as of the date of the Quarterly Report, and has not been updated to reflect events occurring subsequent to the original filing date.

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