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v3.26.1

INVESTMENT IN TRANSMISSION AFFILIATES (Tables) | 6 Months Ended
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Jun. 30, 2026
Transmission Affiliates |
Investment in transmission affiliates |
Schedule of changes to our investments in transmission affiliates | The following tables provide a reconciliation of the changes in our investments in ATC and ATC Holdco:
|  | Three Months Ended June 30, 2026
(in millions) |  | ATC |  | ATC Holdco |  | Total
Balance at beginning of period |  | $ | 2,346.7 |  |  | $ | 22.8 |  |  | $ | 2,369.5 |
Add: Earnings from equity method investment |  | 62.2 |  |  | 0.4 |  |  | 62.6 |
Add: Capital contributions |  | 36.6 |  |  | — |  |  | 36.6 |
Less: Distributions |  | 47.5 |  |  | 0.6 |  |  | 48.1 |
Add: Other |  | 0.1 |  |  | — |  |  | 0.1 |
Balance at end of period |  | $ | 2,398.1 |  |  | $ | 22.6 |  |  | $ | 2,420.7 |
|  | Three Months Ended June 30, 2025
(in millions) |  | ATC |  | ATC Holdco |  | Total
Balance at beginning of period |  | $ | 2,121.6 |  |  | $ | 27.4 |  |  | $ | 2,149.0 |
Add: Earnings from equity method investment |  | 50.3 |  |  | 1.6 |  |  | 51.9 |
Add: Capital contributions |  | 45.5 |  |  | — |  |  | 45.5 |
Less: Distributions |  | 39.9 |  |  | 6.4 |  |  | 46.3 |
Balance at end of period |  | $ | 2,177.5 |  |  | $ | 22.6 |  |  | $ | 2,200.1 |
|  | Six Months Ended June 30, 2026
(in millions) |  | ATC |  | ATC Holdco |  | Total
Balance at beginning of period |  | $ | 2,256.9 |  |  | $ | 23.5 |  |  | $ | 2,280.4 |
Add: Earnings from equity method investment |  | 121.4 |  |  | 0.7 |  |  | 122.1 |
Add: Capital contributions |  | 112.4 |  |  | — |  |  | 112.4 |
Less: Distributions |  | 92.7 |  |  | 1.6 |  |  | 94.3 |
Add: Other |  | 0.1 |  |  | — |  |  | 0.1 |
Balance at end of period |  | $ | 2,398.1 |  |  | $ | 22.6 |  |  | $ | 2,420.7 |
|  | Six Months Ended June 30, 2025
(in millions) |  | ATC |  | ATC Holdco |  | Total
Balance at beginning of period |  | $ | 2,085.1 |  |  | $ | 23.8 |  |  | $ | 2,108.9 |
Add: Earnings from equity method investment |  | 100.3 |  |  | 5.2 |  |  | 105.5 |
Add: Capital contributions |  | 87.8 |  |  | — |  |  | 87.8 |
Less: Distributions |  | 95.7 |  |  | 6.4 |  |  | 102.1 |
Balance at end of period |  | $ | 2,177.5 |  |  | $ | 22.6 |  |  | $ | 2,200.1 |
ATC |
Investment in transmission affiliates |
Schedule of significant related party transactions with ATC | The following table summarizes our significant related party transactions with ATC:
|  | Three Months Ended June 30 |  | Six Months Ended June 30
(in millions) |  | 2026 |  | 2025 |  | 2026 |  | 2025
Charges to ATC for services and construction |  | $ | 6.1 |  |  | $ | 5.0 |  |  | $ | 13.4 |  |  | $ | 9.5 |
Charges from ATC for network transmission services |  | 129.0 |  |  | 116.7 |  |  | 258.2 |  |  | 233.4 |
Net refund (payment) from (to) ATC related to FERC ROE orders |  | (0.7) |  |  | 0.3 |  |  | 1.3 |  |  | 1.7 |
Schedule of receivables and payables with ATC | Our balance sheets included the following receivables and payables for services provided to or received from ATC:
(in millions) |  | June 30, 2026 |  | December 31, 2025
Accounts receivable for services provided to ATC |  | $ | 1.9 |  |  | $ | 1.6 |
Accounts payable for services received from ATC |  | 43.5 |  |  | 38.4 |
Amounts due from ATC for transmission infrastructure upgrades (1) |  | 35.4 |  |  | 32.2 |
(1)These transmission infrastructure upgrades were primarily related to the construction of WE's, WPS's, and UMERC's renewable energy projects.
Schedule of summarized income statement data for ATC | Summarized financial data for ATC is included in the tables below:
|  | Three Months Ended June 30 |  | Six Months Ended June 30
(in millions) |  | 2026 |  | 2025 |  | 2026 |  | 2025
Income statement data |  |  |  |  |  |  |  |
Operating revenues |  | $ | 274.0 |  |  | $ | 241.2 |  |  | $ | 539.3 |  |  | $ | 476.1 |
Operating expenses |  | 129.6 |  |  | 117.6 |  |  | 257.0 |  |  | 234.3 |
Other expense, net |  | 44.7 |  |  | 42.7 |  |  | 88.5 |  |  | 81.8 |
Net income |  | $ | 99.7 |  |  | $ | 80.9 |  |  | $ | 193.8 |  |  | $ | 160.0 |
Schedule of summarized balance sheet data for ATC |
(in millions) |  | June 30, 2026 |  | December 31, 2025
Balance sheet data |  |  |  |
Current assets |  | $ | 163.9 |  |  | $ | 137.5 |
Noncurrent assets |  | 8,139.8 |  |  | 7,590.8 |
Total assets |  | $ | 8,303.7 |  |  | $ | 7,728.3 |
Current liabilities |  | $ | 620.5 |  |  | $ | 839.8 |
Long-term debt |  | 3,576.0 |  |  | 3,156.3 |
Other noncurrent liabilities |  | 782.0 |  |  | 638.9 |
Members' equity |  | 3,325.2 |  |  | 3,093.3 |
Total liabilities and members' equity |  | $ | 8,303.7 |  |  | $ | 7,728.3 |

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