UNITED STATES

SECURITIES AND EXCHANGE COMMISSION

Washington, DC 20549

Form 8-K

CURRENT REPORT

Pursuant to Section 13 or 15(d) of the Securities Exchange Act of 1934

Date of Report (Date of earliest event reported):  August 21, 2018

Proofpoint, Inc.

(Exact name of registrant as specified in its charter)

(408) 517-4710

(Registrant’s telephone number, including area code)

(Former name or former address, if changed since last report)

Check the appropriate box below if the Form 8-K filing is intended to simultaneously satisfy the filing obligation of the registrant under any of the following provisions:

o                 Written communications pursuant to Rule 425 under the Securities Act (17 CFR 230.425)

o                 Soliciting material pursuant to Rule 14a-12 under the Exchange Act (17 CFR 240.14a-12)

o                 Pre-commencement communications pursuant to Rule 14d-2(b) under the Exchange Act (17 CFR 240.14d-2(b))

o                 Pre-commencement communications pursuant to Rule 13e-4(c) under the Exchange Act (17 CFR 240.13e-4(c))

Indicate by check mark whether the registrant is an emerging growth company as defined in Rule 405 of the Securities Act of 1933 (§230.405 of this chapter) or Rule 12b-2 of the Securities Exchange Act of 1934 (§240.12b-2 of this chapter).

Emerging growth company   o

If an emerging growth company, indicate by check mark if the registrant has elected not to use the extended transition period for complying with any new or revised financial accounting standards provided pursuant to Section 13(a) of the Exchange Act.   o

Item 8.01                   Other Events.

Proofpoint, Inc. (“Proofpoint”) issued a notice of redemption to the holders of its outstanding 0.75% Senior Convertible Notes due 2020 (the “Convertible Notes”) on August 21, 2018, pursuant to which it will redeem the outstanding Convertible Notes for cash at a price of 100% of the principal amount of the Convertible Notes, plus accrued and unpaid interest, if any (“the Redemption”), on September 25, 2018, unless earlier converted. Prior to the consummation of the Redemption, the holders of the Convertible Notes are entitled to convert to shares of Proofpoint Common Stock at a rate of 12.7402 shares per $1,000 principal amount of Convertible Notes. In the event any holder delivers a conversion notice as provided in the indenture, Proofpoint intends to satisfy its conversion obligation with respect to each $1,000 principal amount of Notes tendered by delivering shares of its common stock. As of August 21, 2018, $230,000,000 aggregate principal amount of the Convertible Notes were outstanding.  A copy of the notice of redemption is attached to this Current Report on Form 8-K as Exhibit 99.1 and is incorporated herein by reference.

Item 9.01                   Financial Statements and Exhibits.

(d)                                 Exhibits.

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SIGNATURES

Pursuant to the requirements of the Securities Exchange Act of 1934, the registrant has duly caused this report to be signed on its behalf by the undersigned hereunto duly authorized.

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