What changed in this filing

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Item 2. Properties

2025-02-25 compared with 2024-02-08 · 52 added, 49 removed, 312 unchanged (24% of the section changed)

The following map shows the locations of our operations and corporate headquarters as of December 31, 2023:

The following map shows the locations of our active operations and corporate headquarters as of December 31, 2024:

CORPORATE OFFICES

4 unchanged sentences

We own office space located in Burns Harbor, Indiana and our Research and Innovation Center located in Middletown, Ohio.

31 | CLF 2024 FORM 10-K

Location Raw Material

(Tons in millions) State Iron Ore Capacity (lt) HBI Capacity (mt) Coke Capacity (nt) Coal Capacity (nt) Scrap Capacity (mt)

(Tons in millions) State /Province Iron Ore Capacity (lt) HBI Capacity (mt) Coke Capacity (nt) Coal Capacity (nt) Scrap Capacity (mt)

Hibbing Taconite MN l 7.0

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Burns Harbor (Coke) IN l 1.8

Hamilton Works (Coke) ON l 0.7

Lake Erie Works (Coke) ON l 0.7

Monessen PA l 0.3

2 unchanged sentences

FPT Multiple l N/A

29 | CLF 2023 FORM 10-K

Location Raw Steel Processing and Finishing

(Tons in millions) State BF-BOF EAF Configured Capacity (nt) Hot-Rolled Cold-Rolled Coated Stainless & Electrical Plate Slab & Other

Burns Harbor IN l

(Tons in millions) State / Province BF-BOF EAF Configured Capacity (nt) Hot-Rolled Cold-Rolled Coated Stainless & Electrical Plate Slab & Other

Burns Harbor IN l 5.0 l l l l

Burns Harbor Plate IN l

Cleveland Works OH l

Coatesville PA l

Butler PA l 0.4 l

Cleveland Works OH l 3.4 l l l l

Coatesville PA l 0.2 l l

Columbus OH l

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Coshocton OH l

Dearborn Works MI l

Dearborn Works MI l 3.0 l l l

Gary Plate IN l

Indiana Harbor Works IN l

Mansfield Works OH l

Middletown Works OH l

Hamilton Works ON l l l

Indiana Harbor Works IN l 4.0 l l l l

Lake Erie Works ON l 2.5 l

Mansfield Works OH l 0.5 l

Middletown Works OH l 3.0 l l l l l

New Carlisle IN l l

Piedmont NC l

Riverdale IL l

Riverdale IL l 0.7 l

Rockport Works IN l l l

Steelton PA l

Tek & Kote IN l l

Weirton WV l l

Steelton PA l 0.3 l

Zanesville OH l

STEELMAKING AND FINISHING FACILITIES

Our primary steel producing and finishing facilities are located across Illinois, Indiana, Michigan, Ohio, Pennsylvania and West Virginia.

We operate seven blast furnaces and five EAFs on nine properties.

Our primary steel producing and finishing facilities are located across Illinois, Indiana, Michigan, Ohio, Pennsylvania, and Ontario.

We operate eight blast furnaces and five EAFs.

Finishing is completed on site at our integrated operations or at one of our 10 stand-alone processing and finishing facilities.

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During the years ended December 31, 2024 and 2023, FPT processed approximately 3 million net tons of scrap metal, of which approximately 50% of total output was prime grade.

32 | CLF 2024 FORM 10-K

DIRECT REDUCTION PLANT

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IRON ORE MINES AND PELLET PLANTS

The following information concerning our mining properties has been prepared in accordance with the requirements of subpart 1300 of Regulation S-K, which first became applicable to us for the fiscal year ended December 31, 2021.

These requirements differ significantly from the previously applicable disclosure requirements of SEC Industry Guide 7.

Among other differences, subpart 1300 of Regulation S-K requires us to disclose our mineral resources, in addition to our mineral reserves, as of the end of our most recently completed fiscal year both in the aggregate and for each of our individually material mining properties.

The following information concerning our mining properties has been prepared in accordance with the requirements of subpart 1300 of Regulation S-K.

As used in this Annual Report on Form 10-K, the terms “mineral resource,” “measured mineral resource,” “indicated mineral resource,” “inferred mineral resource,” “mineral reserve,” “proven mineral reserve,” and “probable mineral reserve” are defined and used in accordance with subpart 1300 of Regulation S-K.

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Likewise, investors are cautioned not to assume that all or any part of measured or indicated mineral resources will ever be converted to mineral reserves.

30 | CLF 2023 FORM 10-K

See Part I – Item 1A.

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We currently own or co-own and operate five production-stage iron ore mines in Michigan and Minnesota, as well as one indefinitely idled mine in Michigan.

Following the AM USA Transaction, we now have an aggregate annual production capacity of approximately 28 million long tons of iron ore pellets, including our 85.3% share of the Hibbing mine production.

We have an aggregate annual production capacity of approximately 29 million long tons of iron ore pellets, including our 85.3% share of the Hibbing mine production.

Our iron ore mines produce from deposits located within the Biwabik and Negaunee Iron Formation, which are classified as Lake Superior type iron formations that formed under similar sedimentary conditions in shallow marine basins approximately two billion years ago.

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The Northshore mine restarted production in the second quarter of 2023.

33 | CLF 2024 FORM 10-K

The following provides an overview of our iron ore properties:

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All of our iron ore mining operations grant leases, licenses and easements for various purposes, including miscellaneous community land uses, utility infrastructure and other third-party uses, that encumber our properties but do not materially inhibit operations.

Certain assets also serve as collateral securing obligations under our ABL Facility and our senior secured notes.

Certain assets also serve as collateral securing obligations under our ABL Facility.

We maintain the requisite state and federal permits and are in material compliance with all material permits.

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The mining and processing operation is located between latitude 47°25’48” N and 47°31’48” N and longitude 93°04’54” W and 92°54’36” W.

31 | CLF 2023 FORM 10-K

Mining began in 1976 as a joint venture between Bethlehem Steel Corporation and Steel Company of Canada.

Cliffs first became involved in the joint venture when it purchased Pickands Mather's 15% share in 1986.

Prior to the AM USA Transaction, we owned 23% of Hibbing, ArcelorMittal USA had a 62.3% interest and U.S.

Prior to the AM USA Transaction, we owned 23% of Hibbing, ArcelorMittal USA LLC had a 62.3% interest and U.

Steel had a 14.7% interest.

8 unchanged sentences

The net book value of our ownership of Hibbing's property, plant and equipment was $44 million as of December 31, 2024.

For more information, see Exhibit 96.1, the Technical Report Summary on the Hibbing Taconite Property, Minnesota, USA, prepared for the Company by the QP, SLR, with an effective date of December 31, 2021.

For further information, see Exhibit 96.1, the Technical Report Summary on the Hibbing Taconite Property, Minnesota, USA, prepared for the Company by the QP, SLR, with an effective date of December 31, 2021.

Minorca (100% owned) is located in the center of Minnesota’s Mesabi Iron Range.

The Laurentian Pit is located near the City of Gilbert, Minnesota at latitude 47°30'0"N and longitude 92°26’30"W, East 1 Pit is located at latitude 47°31'30"N and longitude 92°23’30"W, and East 2 Pit is located just west of the City of Biwabik at latitude 47°32'0"N and longitude 92°22’30"W.

The Minorca plant is located approximately seven miles to the northeast, near the town of Virginia, Minnesota at latitude 47°33'30"N and longitude 92°31.5'30"W.

The Minorca plant is located approximately seven miles to the northwest, near the town of Virginia, Minnesota at latitude 47°33'30"N and longitude 92°31.5'30"W.

Operations commenced in 1976 as an asset of Inland Steel Company.

In 1998, Ispat International purchased Inland Steel and, in 2004, merged with LNM Holdings and International Steel Group to form Mittal Steel, which in 2007 merged with Arcelor to form ArcelorMittal.

In 1998, Ispat International purchased Inland Steel and, in 2004, merged with LNM Holdings and International Steel Group to form Mittal Steel, which in 2007 merged with Arcelor to form ArcelorMittal S.A.

Minorca has been wholly owned by Cliffs since the 2020 AM USA Transaction.

34 | CLF 2024 FORM 10-K

Minorca holds 13,690 acres of surface rights, of which 282 acres are associated with mineral leases.

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The net book value of Minorca's property, plant and equipment was $208 million as of December 31, 2024.

For more information, see Exhibit 96.2, Technical Report Summary on the Minorca Property, Minnesota, USA, prepared for the Company by the QP, SLR, with an effective date of December 31, 2021.

32 | CLF 2023 FORM 10-K

For further information, see Exhibit 96.2, Technical Report Summary on the Minorca Property, Minnesota, USA, prepared for the Company by the QP, SLR, with an effective date of December 31, 2021.

Northshore's (100% owned) mine is located on the northeastern edge of the Mesabi Iron Range in northeastern Minnesota, approximately four miles southeast of Babbitt, Minnesota at latitude 47°40'12.15"N and longitude 91°53'1.28"W.

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The net book value of Northshore's property, plant and equipment was $230 million as of December 31, 2024.

For more information, see Exhibit 96.3, Technical Report Summary on the Northshore Property, Minnesota, USA, prepared for the Company by the QP, SLR, with an effective date of December 31, 2021.

For further information, see Exhibit 96.3, Technical Report Summary on the Northshore Property, Minnesota, USA, prepared for the Company by the QP, SLR, with an effective date of December 31, 2021.

35 | CLF 2024 FORM 10-K

Tilden (100% owned) is located in Marquette County in Michigan’s Upper Peninsula, on the Marquette Iron Range, approximately five miles south of the city of Ishpeming, Michigan at latitude 46° 29' N and longitude 87° 40' W.

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The net book value of Tilden's property, plant and equipment was $256 million as of December 31, 2024.

For more information, see Exhibit 96.5, Technical Report Summary on the Tilden Property, Michigan, USA, prepared for the Company by the QP, SLR, with an effective date of December 31, 2021.

33 | CLF 2023 FORM 10-K

For further information, see Exhibit 96.5, Technical Report Summary on the Tilden Property, Michigan, USA, prepared for the Company by the QP, SLR, with an effective date of December 31, 2021.

UNITED TACONITE

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The net book value of United Taconite's property, plant and equipment was $570 million as of December 31, 2024.

For more information, see Exhibit 96.4, Technical Report Summary on the United Taconite Property, Minnesota, USA, prepared for the Company by the QP, SLR, with an effective date of December 31, 2021.

For further information, see Exhibit 96.4, Technical Report Summary on the United Taconite Property, Minnesota, USA, prepared for the Company by the QP, SLR, with an effective date of December 31, 2021.

36 | CLF 2024 FORM 10-K

MINERAL RESOURCES

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All mineral resource estimates were reviewed and validated by the QP, SLR.

34 | CLF 2023 FORM 10-K

The following represents iron ore mineral resources, exclusive of mineral reserves, as of December 31, 2024 and 2023:

Iron Ore Mineral Resources

Measured Indicated Measured + Indicated Process Inferred

(In millions of long tons) Tonnage % Grade Tonnage % Grade Tonnage % Grade Recovery Tonnage % Grade

Measured Indicated Measured + Indicated Process Recovery Inferred

(In millions of long tons) Tonnage % Grade Tonnage % Grade Tonnage % Grade Tonnage % Grade

Total Iron Ore 1,351 22.5 1,483 23.6 2,834 23.1 31% 420 32.4

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1 Hibbing is reported at 85.3% based on our ownership level.

2 Incremental adjustments to Hibbing’s mineral reserves are due to acquisition of new leases and mining permits both within and directly adjacent to Hibbing's current operating footprint, as well as reconciliation of the previous four years of depletion with increased levels of dilution.

Reference point selected by the QP is the saleable tons based on the process recovery.

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Mineral Reserves are reported at a $90.00/lt wet standard pellet price freight-on-board (FOB) Lake Superior, which is based on the mine planning model's three-year trailing average of the realized product revenue rate.

Overall, mineral reserves estimates as of December 31, 2023, as compared to the prior-year period, decreased by 3%, which was driven by mining depletion.

Overall, mineral reserves estimates as of December 31, 2024, as compared to the prior-year period, decreased by 1%, which was driven by mining depletion offset by the Hibbing mine plan update.

INTERNAL CONTROLS DISCLOSURE

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Temporary core storage is located at each site’s secure logging facility.

Depending on the mining operation, unused sample reserves, parts, concentrates and splits are securely stored in labeled boxes or barrels at a Cliffs laboratory facility or logging facility, or via a contracted external laboratory.

Cliffs' QA/QC programs are site-specific and range from in-development to well-developed, long standing protocols that involve formal procedures for the use of crude material standards developed from on-site material, as well as regularly inserted coarse and concentrate duplicate samples, control chart analysis and reporting.

Unused sample reserves, parts, concentrates and splits are securely stored in labeled boxes or barrels at a Cliffs laboratory facility or logging facility.

Cliffs' QA/QC programs are site-specific, well-developed protocols that involve formal procedures for the use of crude material standards developed from on-site material, as well as regularly inserted coarse and concentrate duplicate samples, control chart analysis and reporting.

Cliffs typically uses internal and external labs for geometallurgical analyses that are accredited with ASQ/ANSI ISO-9001:2015 (American Society for Quality/American National Standards Institute) for their system of quality management.

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The QP, SLR, reviewed Cliffs' QA/QC practices and provided recommendations for further work.

Where QA/QC programs are still in

Where QA/QC programs were still in development at that time and prior to resource estimation, Cliffs conducted data verification studies utilizing a suite of blind crude ore standards and blind duplicates from historical sample

39 | CLF 2024 FORM 10-K

development and prior to resource estimation, Cliffs conducted data verification studies utilizing a suite of blind crude ore standards and blind duplicates from historical sample reserves within the LoM plan.

reserves within the LoM plan.

Where unaccredited labs provided data used in resource estimation, check lab studies were initiated to verify analytical results.

Cliffs is currently working toward aligning QA/QC protocols at each mine to the Company’s current best practice.

Cliffs is currently working toward completing alignment of QA/QC protocols at each mine to the Company’s current best practice by formalizing procedures.

Cliffs maintains exploration drill hole data in an externally-managed, access-controlled acQuire database that is backed up online at regularly scheduled intervals to provide data redundancy and security.

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We own 60% of the mineral rights and lease 40% via multiple mineral leases having varying expiration dates.

Mining leases routinely are renegotiated and renewed as they approach their respective expiration dates.

Princeton's operations consist of three open-pit surface mines, two underground mines, a preparation plant and two rail loadouts.

Mining leases are routinely renegotiated and renewed as they approach their respective expiration dates.

Princeton's operations consist of three open-pit surface mines, one underground mine, a preparation plant and two rail loadouts.

Our Monessen and Warren facilities produce furnace coke and related by-products in Monessen, Pennsylvania and Warren, Ohio, respectively.

We also operate a cokemaking facility located within Burns Harbor.

We also operate cokemaking facilities located within our Burns Harbor, Lake Erie Works and Hamilton Works locations.

These facilities have an aggregate annual rated capacity of 4.0 million net tons.

During the years ended December 31, 2023 and 2022, our cokemaking facilities produced 2.4 million and 2.1 million net tons of coke, respectively.

During each of the years ended December 31, 2024 and 2023, our cokemaking facilities produced 2.4 million net tons of coke.

OTHER BUSINESSES

Our Tubular operating segment consists of our subsidiary Tubular Components, which has plants in Walbridge, Ohio and Columbus, Indiana.

The Walbridge plant operates six electric resistance welded tube mills on owned property.

The Walbridge plant operates six electric resistance welded tube mills and one laser re-cutting line on owned property.

The Columbus plant operates five electric resistance welded tube mills and four high-speed cold saws on leased property.

Our Tooling and Stamping operating segment consists of our subsidiary Tooling and Stamping and its related companies, which provides advanced-engineered solutions, tool design and build, hot- and cold-stamped steel components and complex assemblies for the automotive market across ten plants, of which certain of these are under long-term lease agreements, in Ontario, Alabama, Kentucky and Tennessee.

Our Tooling and Stamping operating segment consists of our subsidiary Tooling and Stamping and its related companies, which provides advanced-engineered solutions, tool design and build, hot- and cold-stamped steel components and complex assemblies for the automotive market across 10 plants, of which certain of these are under long-term lease agreements, in Ontario, Alabama, Kentucky and Tennessee.

Its facilities feature eight large-bed, hot-stamping presses, providing 14 lines of production;

8 unchanged sentences

Compared sentence by sentence after normalising whitespace, quotation marks, case and digits, so re-formatting and restated figures do not read as changed language. Wording changes appear as one removal and one addition. The current filing and the prior one are authoritative.

What changed 10-K

Item 2. Properties