| DEBT AND CREDIT FACILITIES | 
 NOTE 7 - DEBT AND CREDIT FACILITIES 
The following represents a summary of our long-term debt: 
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| (In millions) |  
| Debt Instrument | 
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Issuer1
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Annual Effective  Interest Rate | 
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March 31, 2023 | 
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December 31, 2022 | 
 
| Senior Secured Notes: | 
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6.750% 2026 Senior Secured Notes  | 
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Cliffs | 
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6.99% | 
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$ | 
829 
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$ | 
829  | 
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| Senior Unsecured Notes: | 
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7.000% 2027 Senior Notes  | 
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Cliffs | 
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9.24% | 
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73 
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73  | 
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7.000% 2027 AK Senior Notes  | 
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AK Steel | 
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9.24% | 
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56 
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56  | 
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5.875% 2027 Senior Notes  | 
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Cliffs | 
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6.49% | 
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556 
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556  | 
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4.625% 2029 Senior Notes   | 
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Cliffs | 
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4.63% | 
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368 
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368  | 
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4.875% 2031 Senior Notes  | 
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Cliffs | 
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4.88% | 
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325 
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325  | 
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6.250% 2040 Senior Notes  | 
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Cliffs | 
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6.34% | 
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235 
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235  | 
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| ABL Facility | 
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Cliffs2
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Variable3
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2,171 
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1,864  | 
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| Total principal amount | 
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4,613 
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4,306  | 
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| Unamortized discounts and issuance costs | 
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(54) | 
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(57) | 
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| Total long-term debt | 
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$ | 
4,559 
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$ | 
4,249  | 
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1 Unless otherwise noted, references in this column and throughout this NOTE 7 - DEBT AND CREDIT FACILITIES to "Cliffs" are to Cleveland-Cliffs Inc., and references to "AK Steel" are to AK Steel Corporation (n/k/a Cleveland-Cliffs Steel Corporation).
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2 Refers to Cleveland-Cliffs Inc. as borrower under our ABL Facility.
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3 Our ABL Facility annual effective interest rate was 6.40% and 5.60%, respectively, as of March 31, 2023 and December 31, 2022.
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Subsequent to the quarter ended March 31, 2023, we issued $750 million aggregate principal amount of 6.750% 2030 Senior Notes.  We used the net proceeds from the offering to repay a portion of the borrowings under our ABL Facility.  Refer to NOTE 18 - SUBSEQUENT EVENTS for further information. 
ABL FACILITY 
As of March 31, 2023, we were in compliance with the ABL Facility liquidity requirements and, therefore, the springing financial covenant requiring a minimum fixed charge coverage ratio of 1.0 to 1.0 was not applicable.  
The following represents a summary of our borrowing capacity under the ABL Facility: 
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| (In millions) | 
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March 31, 2023 | 
 
Available borrowing base on ABL Facility1
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$ | 
4,500 
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| Borrowings | 
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(2,171) | 
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Letter of credit obligations2
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(147) | 
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| Borrowing capacity available | 
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$ | 
2,182 
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1 As of March 31, 2023, the ABL Facility has a maximum available borrowing base of $4.5 billion.  The borrowing base is determined by applying customary advance rates to eligible accounts receivable, inventory and certain mobile equipment.
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2 We issued standby letters of credit with certain financial institutions in order to support business obligations, including, but not limited to, workers' compensation, employee severance, insurance, operating agreements and environmental obligations.
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DEBT MATURITIES 
The following represents a summary of our maturities of debt instruments based on the principal amounts outstanding at March 31, 2023 (in millions):  
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| 2023  | 
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2024 | 
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2025 | 
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2026 | 
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2027 | 
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Thereafter | 
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Total | 
 
| $ | 
—  | 
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$ | 
—  | 
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$ | 
2,171  | 
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$ | 
829  | 
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$ | 
685  | 
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$ | 
928  | 
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$ | 
4,613  | 
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