Exhibit 99.8

From: Mark Grether

To: AllSizmek.Company@sizmek.com

Subject line: Sizmek to Acquire Rocket Fuel: Valuable Resources for You

Body:

Hi everyone,

I strongly encourage you to join the all-hands company meeting at 10:30am EST today. It will provide you with a better understanding of why we’re entered into a definitive acquisition agreement with Rocket Fuel, along with the benefits for both us and our clients.

In the interim, I’d like to ensure you are equipped with the right resources to help address your questions as well as guide you in your external conversations.

You can find an Internal-Only FAQ (not to be shared with clients or others outside of Sizmek) on Source here. For anyone who was unable to attend the all-hands meeting, this will cover the key points. If you have additional questions, please reach out to your department head or growth@sizmek.com.

We also know your clients and even some prospects will have questions about our definitive acquisition agreement with Rocket Fuel. To help guide your discussions, we’ve created talking points for conversations with your clients. Please review before speaking to any external party to ensure you are using the right language, and to minimize any legal risk associated with sharing the wrong information. We’ll continue to update you with more information that you can share when the deal closes.

The Rocket Fuel acquisition marks great, new opportunities for us, and hope you are excited as I am. While we wait for the deal to close, let’s continue to work hard to exceed our Q3 revenue goals, have fun, and of course deliver impressions that inspire for our clients.

Thanks,

Mark

Cautions Regarding Forward-Looking Statements

This communication contains forward-looking statements regarding future events, including but not limited to the acquisition of Rocket Fuel Inc. (“Rocket Fuel”) by Sizmek Inc. (“Sizmek”), the capabilities of the combined company following the acquisition, and Rocket Fuel’s expectations for its Media Services business and second half financial results. Words such as “expect,” “believe,” “intend,” “plan,” “goal,” “focus,” “anticipate,” and other similar words are also intended to identify forward-looking statements.

These forward-looking statements are subject to a number of risks and uncertainties that may cause actual results to differ materially from the results anticipated by such statements, including, without limitation, due to: uncertainties as to the timing of the tender offer and the acquisition; the possibility that competing offers will be made; the possibility that various closing conditions for the tender offer or the acquisition may not be satisfied or waived, including that a governmental entity may prohibit, delay or refuse to grant approval for the consummation of the acquisition; the effects of disruption from the tender offer or acquisition on Rocket Fuel’s business; the fact that the announcement and pendency of the tender offer and acquisition may make it more difficult to establish or maintain relationships with employees, suppliers and other business partners; the effects of disruption caused by the tender offer or acquisition making it more difficult to maintain relationships with employees, customers, vendors and other business partners; and the risk that stockholder litigation in connection with the tender offer or the acquisition may result in significant costs of defense, indemnification and liability.

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Additional factors that could cause actual results to differ materially from those anticipated are under the caption “Risk Factors” in Rocket Fuel’s Annual Report on Form 10-K filed with the Securities and Exchange Commission (“SEC”) on March 16, 2017 and in subsequent SEC filings. These forward-looking statements are made as of the date of this communication, and Sizmek expressly disclaims any obligation or undertaking to update the forward-looking statements contained herein to reflect events that occur or circumstances that exist after the date on which the statements were made.

Important Additional Information and Where to Find It

In connection with the proposed acquisition of Rocket Fuel, Sizmek, through an affiliate, will commence a tender offer for all of the outstanding shares of Rocket Fuel. The tender offer has not commenced. This communication is for informational purposes only and is neither an offer to purchase nor a solicitation of an offer to sell shares of Rocket Fuel. It is also not a substitute for the tender offer materials that Sizmek will file with the SEC upon commencement of the tender offer. At the time that the tender offer is commenced, Sizmek will file tender offer materials on Schedule TO with the SEC, and Rocket Fuel will file a Solicitation/Recommendation Statement on Schedule 14D-9 with the SEC with respect to the tender offer. THE TENDER OFFER MATERIALS (INCLUDING AN OFFER TO PURCHASE, A RELATED LETTER OF TRANSMITTAL AND CERTAIN OTHER TENDER OFFER DOCUMENTS) AND THE SOLICITATION/RECOMMENDATION STATEMENT WILL CONTAIN IMPORTANT INFORMATION THAT SHOULD BE READ CAREFULLY AND CONSIDERED BY ROCKET FUEL’S STOCKHOLDERS BEFORE ANY DECISION IS MADE WITH RESPECT TO THE TENDER OFFER. Both the tender offer materials and the solicitation/recommendation statement will be made available to Rocket Fuel’s stockholders free of charge. A free copy of the tender offer materials and the solicitation/recommendation statement will also be made available to all of Rocket Fuel’s stockholders by contacting Rocket Fuel at ir@rocketfuel.com or by phone at (650) 481-6082, or by visiting Rocket Fuel’s website (www.rocketfuel.com). In addition, the tender offer materials and the solicitation/recommendation statement (and all other documents filed by Rocket Fuel with the SEC) will be available at no charge on the SEC’s website (www.sec.gov) upon filing with the SEC. ROCKET FUEL’S STOCKHOLDERS ARE ADVISED TO READ THE TENDER OFFER MATERIALS AND THE SOLICITATION/RECOMMENDATION STATEMENT, AS EACH MAY BE AMENDED OR SUPPLEMENTED FROM TIME TO TIME, AND ANY OTHER RELEVANT DOCUMENTS FILED BY SIZMEK OR ROCKET FUEL WITH THE SEC WHEN THEY BECOME AVAILABLE BEFORE THEY MAKE ANY DECISION WITH RESPECT TO THE TENDER OFFER. THESE MATERIALS WILL CONTAIN IMPORTANT INFORMATION ABOUT THE TENDER OFFER, SIZMEK AND ROCKET FUEL.

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