Who owns Calpine?
Calpine is owned by Constellation (the United States, Nasdaq: CEG).[1]
Evidence: Constellation Energy Corporation Annual Report on Form 10-K filed 2026-02-24, SEC EDGAR, 24 February 2026. Verified from filings; last checked .
Key facts
- Current owner
- Constellation Energy Corporation verified
- Owner HQ
- 🇺🇸 United States
- Origin
- 🇺🇸 United States
- Category
- Energy › Power & utilities › Power producers
- Parent ticker
- Nasdaq: CEG
- Last verified
- · 1 sources
About Calpine
Calpine is a power generator that Constellation Energy's 2025 10-K says it acquired in January 2026, including the Geysers geothermal assets, with a fleet that increased its presence in ERCOT.
What Constellation's annual report says about Calpine
Sentences about Calpine from Constellation's latest annual filing[1], copied word for word.
These forward-looking statements include, but are not limited to, statements regarding the acquisition of Calpine Corporation, the pro forma combined company and its operations, strategies and plans, enhancements to investment-grade credit profile, synergies, opportunities and anticipated future performance and capital structure, and expected accretion to earnings per share and free cash flow.
On January 7, 2026, Constellation acquired all of the outstanding equity interests of Calpine in a cash and stock transaction.
Our Business Following the merger with Calpine in January 2026, we are the largest private-sector power producer in the world and the nation's largest producer of clean and reliable energy.
How often Constellation names Calpine in its annual report
A plain count of the times the name appears in the text of each annual report, not counting the start of a sentence. A brand that an owner writes about more is usually one it treats as central. The brand is named more often than it was three years earlier.
Ownership timeline of Calpine
- Current owner Constellation [1] verified
Where Calpine sits in Constellation
Controlling ownership as of . Brands grouped under the entity that owns them; large groups are collapsed.
Open the full Constellation ownership tree →
See the full Constellation brand portfolio (2) →
Other brands owned by Constellation
Constellation controls 2 brands on Brandtree, 2 of them in energy.
Also in energy
Other brands in power producers, and who owns them
The 19 brands in power producers on Brandtree belong to 17 owners. The largest is KEPCO, with 3.
| Brand | Owner | Owner based in |
|---|---|---|
| Korea East-West Power | KEPCO | 🇰🇷 South Korea |
| Acwa | ACWA Power | 🇸🇦 Saudi Arabia |
| Auren Energia | Auren Energia | 🇧🇷 Brazil |
| NorthStar Clean Energy | CMS Energy | 🇺🇸 United States |
| Enel Generación Chile | Enel Chile | 🇨🇱 Chile |
| Engie Brasil Energia | Engie Brasil Energia | 🇧🇷 Brazil |
| Hallador Power | Hallador | 🇺🇸 United States |
| JERA | JERA | 🇯🇵 Japan |
About the owner: Constellation
Constellation is a publicly listed company headquartered in United States. Brandtree records 2 brands under its control, and it is listed as Nasdaq: CEG.
Constellation Energy's 2025 Form 10-K says the company was formed as a wholly owned subsidiary of Exelon for the separation, and describes its acquisition of Calpine completed in January 2026, which added the Geysers geothermal assets and a larger presence in Texas.
Constellation: full profile, brands and acquisition history →
🇺🇸 Calpine and other American brands
Brandtree records a controlling owner for 2,399 brands that began in the United States. 461 of them (19%) are now controlled by a company headquartered in another country; Calpine is not one of them.
- AES Ohio — AES 🇺🇸
- Agway Energy Services — Suburban Propane 🇺🇸
- Alabama Power — Southern Company 🇺🇸
- AmeriGas — UGI 🇺🇸
- American Transmission Company — WEC Energy Group 🇺🇸
- Arch Resources — Core Natural Resources 🇺🇸
Frequently asked questions
Who is the parent company of Calpine?
The parent company of Calpine is Constellation, a publicly listed company headquartered in the United States.
Is Calpine American?
Yes. Calpine originated in the United States and its owner, Constellation, is also headquartered in the United States.
Is Calpine still owned by Constellation?
Yes. As of 11 October 2026, Calpine is still owned by Constellation. The ownership record was last checked against primary sources on that date.
Sources (1) & corrections
Last verified . Every ownership fact above is backed by one of these primary documents. Numbers in brackets in the text refer to this list.
- [1] Constellation Energy Corporation Annual Report on Form 10-K filed 2026-02-24 — SEC EDGAR, SEC Form 10-K, published 24 February 2026; retrieved 5 October 2026.
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