UNITED STATES

SECURITIES AND EXCHANGE COMMISSION

Washington, D.C. 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): May 21, 2015

FLOWSERVE CORPORATION

(Exact Name of Registrant as Specified in its Charter)

(972) 443-6500

(Registrant’s telephone number, including area code)

N/A

(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:

The information provided in Item 5.03 of this Current Report on Form 8-K regarding an amendment to the Flowserve Corporation By-Laws (the “Bylaws”) is incorporated by reference into this Item 3.03.

On May 21, 2015, the Board of Directors of Flowserve Corporation, a New York Corporation (the “Company”) voted to amend the Bylaws, effective May 21, 2015. Article III, Section 2 of the Bylaws, which sets forth the number of directors of the Company, was amended by the Board of Directors to reduce the number of directors of the Company from twelve to eleven.

The foregoing description of the amendment contained in the Bylaws is qualified in its entirety by reference to the full text of, and should be read in conjunction with, the Bylaws, a copy of which is filed with this Current Report on Form 8-K as Exhibit 3.1 and incorporated herein by reference.

On May 21, 2015, the Company held its 2015 Annual Meeting of Shareholders (the “Meeting”). The number of shares present at the Meeting was 122,613,204 representing 91.03% of the 134,690,823 shares issued and outstanding that were entitled to vote on March 26, 2015, the record date for the Meeting.

Five items of business were submitted to shareholders at the Meeting. The voting results for each proposal are set forth below:

1. Election of Directors. The director nominees listed below were duly elected at the Meeting for annual terms expiring in 2016 pursuant to the following votes:

The foregoing totals of votes for and withheld do not include broker non-votes.

2. Advisory Vote on Executive Compensation. The proposal for approval, on an advisory basis, of the compensation of the Company’s named executive officers was approved pursuant to the following votes:

3. Re-approval of the Flowserve Corporation Equity and Incentive Compensation Plan Performance Measures. The material terms of the performance measures available under the Flowserve Corporation Equity Incentive Compensation Plan were approved pursuant to the following votes:

4. Ratification of Independent Registered Public Accounting Firm. PricewaterhouseCoopers LLP was ratified to serve as the Company’s independent registered public accounting firm for 2015 pursuant to the following votes:

5. Shareholder Proposal – Shareholder Action by Written Consent. The shareholder proposal requesting that shareholders be given the right to act by written consent outside of an annual or special meeting was rejected pursuant to the following votes:

No other matters were voted on at the Meeting.

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.

EXHIBIT INDEX