CPST Capstone Turbine Corporation

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) April 16, 2015 (April 10, 2015)

CAPSTONE TURBINE CORPORATION

(Exact name of registrant as specified in its charter)

(818) 734-5300

(Registrant’s telephone number, including area code)

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))

Item 5.02. Departure of Directors or Certain Officers; Election of Directors; Appointment of Certain Officers; Compensatory Arrangements of Certain Officers.

On April 10, 2015, Capstone Turbine Corporation (the “Company”) announced that Edward I. Reich, the Executive Vice President and Chief Financial Officer of the Company, would be leaving the Company to pursue other opportunities, effective immediately. Mr. Reich will continue to serve the Company in a consulting capacity until May 10, 2016. On April 11, 2015, Mr. Reich and the Company entered into a General Release and Separation Agreement (the “Separation Agreement”), which provides for, among other things, severance payments to Mr. Reich equal to 12 months of Mr. Reich’s salary immediately prior to the termination of his employment, payable in accordance with the Company’s regular payroll practices. The Separation Agreement also includes a general release of the Company and its affiliates by Mr. Reich.

On April 10, 2015, effective immediately, Jayme L. Brooks, the Vice President of Finance and Chief Accounting Officer of the Company, was promoted to Chief Financial Officer in addition to her role as Chief Accounting Officer of the Company. Ms. Brooks has served as the Company’s Vice President of Finance and Chief Accounting Officer since November 2008. She served as Vice President of Financial Planning and Analysis of the Company from February 2008 to November 2008. She also served as Interim Chief Accounting Officer from October 2008 to November 2008. She joined the Company in September 2005 and served as Director of Financial Reporting from September 2005 until February 2008. Ms. Brooks holds a Bachelor of Arts degree in Business Economics from the University of California at Santa Barbara and a Master of Business Administration degree from the Fuqua School of Business at Duke University. Ms. Brooks is a Certified Public Accountant licensed in California and a member of Financial Executives International.

In connection with her appointment, the Company’s Compensation Committee increased Ms. Brook’s annual salary from $225,000 to $247,500. Ms. Brooks is also eligible for a target bonus of 45% of her base salary at the discretion of the Compensation Committee if certain performance goals are achieved. In addition, Ms. Brooks will receive a stock option grant to purchase 107,700 shares of the Company’s common stock pursuant to the Company’s 2000 Equity Incentive Plan with an exercise price of $0.64, the closing market price of the Company’s common stock on April 13, 2015. The options expire in ten years with 25% vesting on the first anniversary of the grant date and the remaining options vesting pro-rata each month over the next 36 months. Ms. Brooks also received a grant of 40,000 restricted stock units that vest in increments of 25% on each anniversary of the grant date.

On April 10, 2015, the Company issued a press release regarding the foregoing changes in organizational structure. A copy of the press release is furnished as Exhibit 99 to this Current Report on Form 8-K and is incorporated herein by reference in its entirety.

Item 9.01. Financial Statements and Exhibits.

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SIGNATURE

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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EXHIBIT INDEX

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Exhibit 99

Capstone Flattens Organizational Structure to Lower Cost, Increase Adaptability as well as Foster Innovation and Creativity

CHATSWORTH, Calif., April 10, 2015 (GLOBE NEWSWIRE) — Capstone Turbine Corporation (www.capstoneturbine.com) (Nasdaq: CPST), the world’s leading clean technology manufacturer of microturbine energy systems, announced today that it has flattened its organizational structure to lower operating costs, increase adaptability as well as foster more innovation and creativity.

The new organizational structure will eliminate three executive positions and will save the company an estimated $2 million annually in salaries equity, benefits, bonuses, and travel costs after payment of associated employee severance benefits.

As one part of the organizational change, Capstone’s Executive Vice President and Chief Financial Officer (CFO) Edward Reich will be leaving the company to seek other opportunities. Jayme Brooks has been newly promoted to Chief Financial Officer and Chief Accounting Officer from her long-standing role as the company’s Vice President Finance and Chief Accounting Officer as the two positions are being merged into one leadership role under the new structure.

Flat organizational structures feature less layers of management where employees are more empowered and are expected to take on a range of responsibility for what would be traditionally considered managerial decisions in their daily work routines. In flat organizations lower-level employees are often included in the corporate goal-setting processes and are motivated to help the company reach those goals. This shared process cultivates accountability, encourages better communication, promotes organizational flexibility and improves overall response times to meet project deadlines.

These types of organizations tend to be more adaptable, due to their smaller hierarchies and reduced bureaucracies. When front-line employees are empowered to make higher-level decisions on projects, for example, they can often craft their own unique operational solution without seeking the approval of upper management, thus streamlining the workflow.

“Open communication and collaboration should improve under this new organizational structure since more responsibility will now be placed upon each individual; creating a situation where innovative and collaborative self-starters will excel. In addition, we can attract the type of employees who are encouraged by a work structure that requires self-motivation and cross-functional teamwork,” said Darren Jamison, President and Chief Executive Officer at Capstone Turbine.

“In light of the macroeconomic headwinds in oil, currency exchange and geopolitical issues affecting our business over the past year, I felt all the more compelled to flatten our organization and center our focus on improving our current products, broadening our aftermarket services and leaning our internal operations to achieve our short-term goal of EBITDA breakeven,” added Jamison.

About Capstone Turbine Corporation

Capstone Turbine Corporation (www.capstoneturbine.com) (Nasdaq:CPST) is the world’s leading producer of low-emission microturbine systems and was the first to market commercially viable microturbine energy products. Capstone Turbine has shipped approximately 8,000 Capstone Microturbine systems to customers worldwide. These award-winning systems have logged millions of documented runtime operating hours. Capstone Turbine is a member of the U.S. Environmental Protection Agency’s Combined Heat and Power Partnership, which is committed to improving the efficiency of the nation’s energy infrastructure and reducing emissions of pollutants and greenhouse gases. A UL-Certified ISO 9001:2008 and ISO 14001:2004 certified company, Capstone is headquartered in the Los Angeles area with sales and/or service centers in the New York Metro Area, United Kingdom, Mexico City, Shanghai and Singapore.

The Capstone Turbine Corporation logo is available at http://www.globenewswire.com/newsroom/prs/?pkgid=6212

This press release contains “forward-looking statements,” as that term is used in the federal securities laws, about the advantages of our new organizational structure. Forward-looking statements may be identified by words such as “expects,” “objective,” “intend,” “targeted,” “plan” and similar phrases. These forward-looking statements are subject to numerous assumptions, risks and uncertainties described in Capstone’s filings with the Securities and Exchange Commission that may cause Capstone’s actual results to be materially different from any future results expressed or implied in such statements. Capstone cautions readers not to place undue reliance on these forward-looking statements, which speak only as of the date of this release. Capstone undertakes no obligation, and specifically disclaims any obligation, to release any revisions to any forward-looking statements to reflect events or circumstances after the date of this release or to reflect the occurrence of unanticipated events.

“Capstone” and “Capstone MicroTurbine” are registered trademarks of Capstone Turbine Corporation. All other trademarks mentioned are the property of their respective owners.

Capstone Turbine Corporation

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