Spark Therapeutics, Inc. (ONCE) Information Request Form

Levi & Korsinsky, LLP has commenced an investigation into the fairness of the sale of Spark Therapeutics, Inc. (NASDAQGS: ONCE) to Roche (OTCQX: RHHBY). Under the terms of the transaction, Spark Therapeutics shareholders will receive US$114.50 per share.

The Spark merger investigation concerns whether the Board of Spark breached their fiduciary duties to stockholders by failing to adequately shop the Company before agreeing to enter into this transaction, and whether Roche is underpaying for Spark shares, thus unlawfully harming Spark shareholders.

To receive more information, please fill out the form.

Levi & Korsinsky, LLP does not share your information with others. There is no cost or obligation for you to submit.

This submission does not create an attorney-client relationship. If we believe that you might be an appropriate lead plaintiff, we will contact you to discuss whether to establish an attorney-client relationship.

Yes I'd Like to Join Action

This letter confirms that you have retained Levi & Korsinsky, LLP to represent you as a named plaintiff in the class action against Spark Therapeutics, Inc. As a named plaintiff, you acknowledge that you owned shares in Spark Therapeutics, Inc. prior to the recent takeover announcement and that you must maintain ownership in Spark Therapeutics, Inc. throughout the litigation.

We agree to advance all expenses in the litigation, which means that you are not liable to pay any of the expenses of the lawsuit, whether attorneys’ fees or costs. Regardless of the result, we will never ask you to directly pay for any attorneys’ fees or costs. Should we obtain a favorable result, we may ask the court to award us compensation to be paid by the defendants or as a portion of any benefit, but, again, we will never ask you to directly pay any of the costs of this litigation.

As our client, you are entitled to direct the litigation in any way you deem proper, and may at any time order us to dismiss the case. Should you choose to do so, we will never ask you to reimburse us directly for any legal fees or expenses. During the course of this litigation, we may employ and/or work with other law firms to prosecute your case.

We look forward to representing you and other Spark shareholders.

Sincerely,

Levi & Korsinsky,LLP

Joseph Levi

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