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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): November 3, 2005
CALPINE CORPORATION
(A Delaware Corporation)
Commission File Number: 001-12079
I.R.S. Employer Identification No. 77-0212977
50 West San Fernando Street
San Jose, California 95113
Telephone: (408) 995-5115
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 (see General Instruction A.2. below):
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))

TABLE OF CONTENTS

| ITEM 2.02. RESULTS OF OPERATIONS AND FINANCIAL CONDITION
| ITEM 9.01. FINANCIAL STATEMENTS AND EXHIBITS
| SIGNATURES
EXHIBIT INDEX
EXHIBIT 99.1
EXHIBIT 99.2

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SECTION 2 — FINANCIAL INFORMATION
ITEM 2.02. RESULTS OF OPERATIONS AND FINANCIAL CONDITION
On November 3, 2005, the Registrant issued the press release attached hereto as Exhibit 99.1 reporting financial and operating results for the quarter ended September 30, 2005. The registrant also attaches Exhibit 99.2 hereto the materials presented in connection with the registrant’s November 3, 2005 earnings conference call and webcast presentation.
SECTION 9 — FINANCIAL STATEMENTS AND EXHIBITS
ITEM 9.01. FINANCIAL STATEMENTS AND EXHIBITS

(a) |  | Financial Statements of Businesses Acquired .
|  | Not Applicable
(b) |  | Pro Forma Financial Information .
|  | Not Applicable
(c) |  | Exhibits .

Exhibit |  | Description
99.1 |  | Press release
99.2 |  | Presentation Materials

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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.

| CALPINE CORPORATION |
| By: | /s/ Charles B. Clark, Jr. |
|  | Charles B. Clark, Jr. |
Date: November 4, 2005 |  | Senior Vice President and Controller Chief Accounting Officer |

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EXHIBIT INDEX

Exhibit |  | Description
99.1 |  | Press release
99.2 |  | Presentation Materials