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Acacia Communications, Inc. (ACIA) Loss Submission Form

The Klein Law Firm announces that a class action complaint has been filed on behalf of shareholders of Acacia Communications, Inc. (NASDAQ: ACIA) who purchased shares between August 11, 2016 and July 13, 2017. The action, which was filed in the United States District Court for the District of Massachusetts, alleges that the Company violated federal securities laws.

In particular, the complaint alleges that (i) the Company’s manufacturing and quality control processes were deficient; (ii) the foregoing deficiencies were likely to disrupt the Company’s manufacturing, thereby impacting the Company’s revenues; and (iii) as a result of the foregoing, Acacia Communications’ public statements were materially false and misleading at all relevant times. On May 31, 2017, Acacia Communications announced it had “identified a quality issue” affecting a fraction of certain units manufactured “by one of its three contract manufacturers over an approximate four month period.” Acacia Communications cited a “circuit board cleaning process” as the “root cause of this quality issue” and the process was eliminated. Then on July 14, 2017, Acacia Communications revealed its preliminary financial and operating results for the quarter ended June 30, 2017, reporting that the “second quarter results were adversely affected by” the previously announced quality issue. The Company also said it “experienced supply constraints” and lowered its guidance for the quarter.

Shareholders have until October 13, 2017 to petition the court for lead plaintiff status. Your ability to share in any recovery does not require that you serve as lead plaintiff. You may choose to be an absent class member.

Keep Me Informed

The Klein Law Firm does not share your information with others. There is no cost or obligation. 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.

This letter confirms that you have retained The Klein Law Firm to represent you as a named plaintiff in a shareholder action involving Acacia Communications, Inc.

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 class benefit, but, again, we will never ask you to directly pay any of the costs of this litigation.

As the 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 or opt-out. 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 Acacia Communications, Inc. shareholders.

Sincerely,

The Klein Law Firm

Joseph Klein

AGREED: Sign Name Clear