CYRN CYREN Ltd

CALCULATION OF FILING FEE

Check the appropriate boxes below to designate any transaction to which the statement relates:

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This Amendment No. 1 (this “ Amendment ”) amends and supplements the Tender Offer Statement on Schedule TO initially filed with the United States Securities and Exchange Commission on November 20, 2017 (together with any amendments and supplements thereto, the “ Schedule TO ”) by WP XII Investments B.V., a private limited liability company organized under the laws of the Netherlands (“WP XII BV”), which is a wholly owned subsidiary of WP XII Investments Coöperatief U.A., a company incorporated in The Netherlands (“WP XII Investments Coöperatief”), which is jointly owned by (i) Warburg Pincus (Callisto) Private Equity XII (Cayman), L.P., a Cayman Islands exempted limited partnership (“ WP XII Callisto ”), (ii) Warburg Pincus (Europa) Private Equity XII (Cayman), L.P., a Cayman Islands exempted limited partnership (“ WP XII Europa ”), (iii) Warburg Pincus (Ganymede) Private Equity XII (Cayman), L.P., a Cayman Islands exempted limited partnership (“ WP XII Ganymede ”), (iv) Warburg Pincus Private Equity XII-B (Cayman), L.P., a Cayman Islands exempted limited partnership (“ WP XII-B ”), (v) Warburg Pincus Private Equity XII-D (Cayman), L.P., a Cayman Islands exempted limited partnership (“ WP XII-D ”), (vi) Warburg Pincus Private Equity XII-E (Cayman), L.P., a Cayman Islands exempted limited partnership (“ WP XII-E ”), (vii) Warburg Pincus XII Partners (Cayman), L.P., a Cayman Islands exempted limited partnership (“ Warburg Pincus XII Partners ”) and (viii) WP XII Partners (Cayman), L.P., a Cayman Islands exempted limited partnership (“ WP XII Partners, ” and together with WP XII Callisto, WP XII Europa, WP XII Ganymede, WP XII-B, WP XII-D, WP XII-E and Warburg Pincus XII Partners, the “ WP XII Funds ”; the WP XII Funds, collectively with WP XII BV and WP XII Investments Coöperatief, the “ Bidder ”) and

relates to the offer by the Bidder to purchase 31,265,358 outstanding ordinary shares, nominal (par) value NIS 0.15 per share (the “Shares”), of Cyren Ltd. (“Cyren”), at $2.50 per Share, net to the seller in cash, less any applicable withholding taxes, and without interest, upon the terms of, and subject to the conditions to, the Offer to Purchase, dated November 20, 2017 (the “Offer to Purchase”) and the related Letter of Transmittal, copies of which are attached to the Schedule TO as Exhibits (a)(1)(A) and (a)(1)(B), respectively (which, together with any amendments or supplements thereto, constitute the “Offer”).

Except as specifically provided herein, the information contained in the Schedule TO, the Offer to Purchase, and the Letter of Transmittal remains unchanged and this Amendment does not modify any of the information previously reported on the Schedule TO. This Amendment should be read in conjunction with the Schedule TO, the Offer to Purchase, and the Letter of Transmittal.

The information set forth in Section 12 (“Legal Matters and Regulatory Approvals”) of the Offer to Purchase is hereby amended and supplemented by adding the following paragraph after the last paragraph under such heading:

“On November 24, 2017, the German Federal Cartel Office granted approval of the Offer in accordance with the Act Against Restraints of Competition and the regulations promulgated thereunder. Accordingly, the portion of the condition relating to obtaining any approvals, licenses, permits or consents applicable to the Offer under the competition laws of Germany and the regulations promulgated thereunder has been satisfied.”

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SIGNATURES

After due inquiry and to the best of the knowledge and belief of the undersigned, the undersigned certify that the information set forth in this statement is true, complete and correct.

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Dated: November 28, 2017

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