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Contingencies and Commitments | 9 Months Ended
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Sep. 30, 2025
Other Commitments [Line Items] |
Contingencies and Commitments | Contingencies and Commitments CMS Energy and Consumers are involved in various matters that give rise to contingent liabilities. Depending on the specific issues, the resolution of these contingencies could negatively affect CMS Energy’s and Consumers’ liquidity, financial condition, and results of operations. In their disclosures of these matters, CMS Energy and Consumers provide an estimate of the possible loss or range of loss when such an estimate can be made. Disclosures stating that CMS Energy or Consumers cannot predict the outcome of a matter indicate that they are unable to estimate a possible loss or range of loss for the matter. CMS Energy Contingencies CMS Land retained environmental remediation obligations for the collection and treatment of leachate at Bay Harbor after selling its interests in the development in 2002. Leachate is produced when water enters into cement kiln dust piles left over from former cement plant operations at the site. In 2012, CMS Land and EGLE finalized an agreement establishing the final remedies and the future water quality criteria at the site. CMS Land completed all construction necessary to implement the remedies required by the agreement and will continue to maintain and operate a system to discharge treated leachate into Little Traverse Bay under an NPDES permit, which is valid through 2025. CMS Land submitted a renewal request in March 2025, and will continue to operate under the existing permit until a renewal is issued. At September 30, 2025, CMS Energy had a recorded liability of $47 million for its remaining obligations for environmental remediation. CMS Energy calculated this liability based on discounted projected costs, using a discount rate of 4.34 percent and an inflation rate of 1 percent on annual operating and maintenance costs. The undiscounted amount of the remaining obligation is $59 million. CMS Energy expects to pay the following amounts for long-term leachate disposal and operating and maintenance costs during the remainder of 2025 and in each of the next five years:
In Millions
| 2025 | 2026 | 2027 | 2028 | 2029 | 2030
Long-term leachate disposal and operating and maintenance costs |  | $ | 1 |  |  | $ | 4 |  |  | $ | 4 |  |  | $ | 4 |  |  | $ | 4 |  |  | $ | 4 |
CMS Energy’s estimate of response activity costs and the timing of expenditures could change if there are changes in circumstances or assumptions used in calculating the liability. Although a liability for its present estimate of remaining response activity costs has been recorded, CMS Energy cannot predict the ultimate financial impact or outcome of this matter. Consumers Electric Utility Contingencies Electric Environmental Matters: Consumers’ operations are subject to environmental laws and regulations. Historically, Consumers has generally been able to recover, in customer rates, the costs to operate its facilities in compliance with these laws and regulations. Cleanup and Solid Waste: Consumers expects to incur remediation and other response activity costs at a number of sites under NREPA. Consumers believes that these costs should be recoverable in rates, but cannot guarantee that outcome. Consumers estimates its liability for NREPA sites for which it can estimate a range of loss to be between $4 million and $5 million. At September 30, 2025, Consumers had a recorded liability of $4 million, the minimum amount in the range of its estimated probable NREPA liability, as no amount in the range was considered a better estimate than any other amount. Consumers is a potentially responsible party at a number of contaminated sites administered under CERCLA. CERCLA liability is joint and several. In 2010, Consumers received official notification from the EPA that identified Consumers as a potentially responsible party for cleanup of PCBs at the Kalamazoo River CERCLA site. The notification claimed that the EPA had reason to believe that Consumers disposed of PCBs and arranged for the disposal and treatment of PCB-containing materials at portions of the site. In 2011, Consumers received a follow-up letter from the EPA requesting that Consumers agree to participate in a removal action plan along with several other companies for an area of lower Portage Creek, which is connected to the Kalamazoo River. All parties asked to participate in the removal action plan, including Consumers, declined to accept liability. Until further information is received from the EPA, Consumers is unable to estimate a range of potential liability for cleanup of the river. Based on its experience, Consumers estimates its share of the total liability for known CERCLA sites to be between $3 million and $8 million. Various factors, including the number and creditworthiness of potentially responsible parties involved with each site, affect Consumers’ share of the total liability. At September 30, 2025, Consumers had a recorded liability of $3 million for its share of the total liability at these sites, the minimum amount in the range of its estimated probable CERCLA liability, as no amount in the range was considered a better estimate than any other amount. The timing of payments related to Consumers’ remediation and other response activities at its CERCLA and NREPA sites is uncertain. Consumers periodically reviews these cost estimates. A change in the underlying assumptions, such as an increase in the number of sites, different remediation techniques, the nature and extent of contamination, and legal and regulatory requirements, could affect its estimates of NREPA and CERCLA liability. Ludington Overhaul Contract Dispute: Consumers and DTE Electric, co-owners of Ludington, entered into a 2010 engineering, procurement, and construction agreement with Toshiba International, under which Toshiba International contracted to perform a major overhaul and upgrade of Ludington. Toshiba International later assigned the contract and all of its obligations to TAES. TAES’ work under the contract was incomplete, defective, and non‑conforming. Consumers and DTE Electric repeatedly documented TAES’ failure to perform under the contract and demanded that TAES provide a comprehensive plan to resolve those matters, including adherence to its warranty commitments and other contractual obligations. Consumers and DTE Electric engaged in extensive efforts to resolve these issues with TAES, including a formal demand to TAES’ parent, Toshiba, under a parent guaranty it provided. TAES did not provide a comprehensive plan or otherwise meet its performance obligations. As a result of TAES’ defaults, Consumers and DTE Electric terminated the contract. In order to enforce their rights under the contract and parent guaranty, and to pursue appropriate damages, Consumers and DTE Electric filed a complaint against TAES and Toshiba in the U.S. District Court for the Eastern District of Michigan in 2022. TAES and Toshiba filed a motion to dismiss the complaint, along with an answer and counterclaims seeking approximately $15 million in damages related to payments allegedly owed under the parties’ contract. As a co-owner of Ludington, Consumers would be liable for 51 percent of any such damages, if liability and damages were proven. The court denied the motion to dismiss filed by TAES and Toshiba. The trial is scheduled to begin in the fourth quarter of 2025. Consumers believes the counterclaims filed by TAES and Toshiba are without merit, but cannot predict the financial impact or outcome of this matter. An unfavorable outcome could have a material adverse effect on CMS Energy’s and Consumers’ financial condition, results of operations, or liquidity. In 2023, Toshiba announced that TBJH became the majority shareholder and new parent company of Toshiba through a common stock purchase. TBJH is a subsidiary of a Japanese private equity firm. Consumers and DTE Electric continue to monitor this development, but do not believe that this affects their rights under the parent guaranty provided by Toshiba. In 2023, the MPSC approved Consumers’ and DTE Electric’s jointly-filed request for authority to defer as a regulatory asset the costs associated with repairing or replacing the defective work performed by TAES while the litigation with TAES and Toshiba moves forward. Although litigation is ongoing, Consumers currently estimates that its share of repair, replacement, and other damages resulting from TAES’ defective work is approximately $350 million, which may be offset in part or entirely by any potential future litigation proceeds received from TAES or Toshiba. Consumers and DTE Electric will have the opportunity to seek appropriate recovery and ratemaking treatment for amounts recorded as a regulatory asset following resolution of the litigation, including any amounts not recovered from TAES or Toshiba. Consumers cannot predict the financial impact or outcome of such proceedings. Consumers Gas Utility Contingencies Consumers expects to incur remediation and other response activity costs at a number of sites under NREPA. These sites include 23 former MGP facilities. Consumers operated the facilities on these sites for some part of their operating lives. For some of these sites, Consumers has no present ownership interest or may own only a portion of the original site. At September 30, 2025, Consumers had a recorded liability of $60 million for its remaining obligations for these sites. Consumers expects to pay the following amounts for remediation and other response activity costs during the remainder of 2025 and in each of the next five years:
In Millions
| 2025 | 2026 | 2027 | 2028 | 2029 | 2030
Remediation and other response activity costs |  | $ | — |  |  | $ | 3 |  |  | $ | 8 |  |  | $ | 25 |  |  | $ | 11 |  |  | $ | 3 |
Consumers periodically reviews these cost estimates. Any significant change in the underlying assumptions, such as an increase in the number of sites, changes in remediation techniques, or legal and regulatory requirements, could affect Consumers’ estimates of annual response activity costs and the MGP liability. Pursuant to orders issued by the MPSC, Consumers defers its MGP-related remediation costs and recovers them from its customers over a ten-year period. At September 30, 2025, Consumers had a regulatory asset of $85 million related to the MGP sites. Guarantees Presented in the following table are CMS Energy’s and Consumers’ guarantees at September 30, 2025:
In Millions
Guarantee Description | Issue Date | Expiration Date | Maximum Obligation | Carrying Amount
CMS Energy, including Consumers |  |  |  |  |  |
Indemnity obligations from sale of membership interests in VIEs 1 | various | various |  | $ | 229 |  |  | $ | — |
Indemnity obligations from stock and asset sale agreements 2 | various | indefinite |  | 152 |  |  | — |
Guarantee 3 | 2011 | indefinite |  | 30 |  |  | — |
Consumers |  |  |  |  |  |
Guarantee 3 | 2011 | indefinite |  | $ | 30 |  |  | $ | — |
1 These obligations arose from the sale of membership interests in Aviator Wind, Newport Solar Holdings, and NWO Holdco to tax equity investors. NorthStar Clean Energy provided certain indemnity obligations that protect the tax equity investors against losses incurred as a result of breaches of representations and warranties under the associated limited liability company agreements. These obligations are generally capped at an amount equal to the tax equity investor’s capital contributions plus a specified return, less any distributions and tax benefits it receives, in connection with its membership interest. For any indemnity obligations related to Aviator Wind, NorthStar Clean Energy would recover 49 percent of any amounts paid to the tax equity investor from the other owner of Aviator Wind Equity Holdings. Additionally, Aviator Wind holds insurance coverage that would partially protect against losses incurred as a result of certain failures to qualify for production tax credits. For further details on NorthStar Clean Energy’s ownership interest in Aviator Wind, Newport Solar Holdings, and NWO Holdco, see Note 11, Variable Interest Entities. 2 These obligations arose from stock and asset sale agreements under which CMS Energy or a subsidiary of CMS Energy indemnified the purchaser for losses resulting from various matters, including claims related to taxes. The maximum obligation amount is mostly related to an Equatorial Guinea tax claim. 3 This obligation comprises a guarantee provided by Consumers to the U.S. Department of Energy in connection with a settlement agreement regarding damages resulting from the department’s failure to accept spent nuclear fuel from nuclear power plants formerly owned by Consumers. Additionally, in the normal course of business, CMS Energy, Consumers, and certain other subsidiaries of CMS Energy have entered into various agreements containing tax and other indemnity provisions for which they are unable to estimate the maximum potential obligation. CMS Energy and Consumers consider the likelihood that they would be required to perform or incur substantial losses related to these indemnities and those disclosed in the table to be remote. Other Contingencies In addition to the matters disclosed in this Note and Note 1, Regulatory Matters, there are certain other lawsuits and administrative proceedings before various courts and governmental agencies, as well as unasserted claims that may result in such proceedings, arising in the ordinary course of business to which CMS Energy, Consumers, and certain other subsidiaries of CMS Energy are parties. These other lawsuits, proceedings, and unasserted claims may involve personal injury, property damage, contracts, environmental matters, federal and state taxes, rates, licensing, employment, and other matters. Certain of these matters, while potentially substantial, are covered by insurance and the insurer or insurers are involved in the relevant proceedings. Further, CMS Energy and Consumers occasionally self-report certain regulatory non‑compliance matters that may or may not eventually result in administrative proceedings. CMS Energy and Consumers believe that the outcome of any one of these proceedings and potential claims will not have a material negative effect on their consolidated results of operations, financial condition, or liquidity.
Consumers Energy Company |
Other Commitments [Line Items] |
Contingencies and Commitments | Contingencies and Commitments CMS Energy and Consumers are involved in various matters that give rise to contingent liabilities. Depending on the specific issues, the resolution of these contingencies could negatively affect CMS Energy’s and Consumers’ liquidity, financial condition, and results of operations. In their disclosures of these matters, CMS Energy and Consumers provide an estimate of the possible loss or range of loss when such an estimate can be made. Disclosures stating that CMS Energy or Consumers cannot predict the outcome of a matter indicate that they are unable to estimate a possible loss or range of loss for the matter. CMS Energy Contingencies CMS Land retained environmental remediation obligations for the collection and treatment of leachate at Bay Harbor after selling its interests in the development in 2002. Leachate is produced when water enters into cement kiln dust piles left over from former cement plant operations at the site. In 2012, CMS Land and EGLE finalized an agreement establishing the final remedies and the future water quality criteria at the site. CMS Land completed all construction necessary to implement the remedies required by the agreement and will continue to maintain and operate a system to discharge treated leachate into Little Traverse Bay under an NPDES permit, which is valid through 2025. CMS Land submitted a renewal request in March 2025, and will continue to operate under the existing permit until a renewal is issued. At September 30, 2025, CMS Energy had a recorded liability of $47 million for its remaining obligations for environmental remediation. CMS Energy calculated this liability based on discounted projected costs, using a discount rate of 4.34 percent and an inflation rate of 1 percent on annual operating and maintenance costs. The undiscounted amount of the remaining obligation is $59 million. CMS Energy expects to pay the following amounts for long-term leachate disposal and operating and maintenance costs during the remainder of 2025 and in each of the next five years:
In Millions
| 2025 | 2026 | 2027 | 2028 | 2029 | 2030
Long-term leachate disposal and operating and maintenance costs |  | $ | 1 |  |  | $ | 4 |  |  | $ | 4 |  |  | $ | 4 |  |  | $ | 4 |  |  | $ | 4 |
CMS Energy’s estimate of response activity costs and the timing of expenditures could change if there are changes in circumstances or assumptions used in calculating the liability. Although a liability for its present estimate of remaining response activity costs has been recorded, CMS Energy cannot predict the ultimate financial impact or outcome of this matter. Consumers Electric Utility Contingencies Electric Environmental Matters: Consumers’ operations are subject to environmental laws and regulations. Historically, Consumers has generally been able to recover, in customer rates, the costs to operate its facilities in compliance with these laws and regulations. Cleanup and Solid Waste: Consumers expects to incur remediation and other response activity costs at a number of sites under NREPA. Consumers believes that these costs should be recoverable in rates, but cannot guarantee that outcome. Consumers estimates its liability for NREPA sites for which it can estimate a range of loss to be between $4 million and $5 million. At September 30, 2025, Consumers had a recorded liability of $4 million, the minimum amount in the range of its estimated probable NREPA liability, as no amount in the range was considered a better estimate than any other amount. Consumers is a potentially responsible party at a number of contaminated sites administered under CERCLA. CERCLA liability is joint and several. In 2010, Consumers received official notification from the EPA that identified Consumers as a potentially responsible party for cleanup of PCBs at the Kalamazoo River CERCLA site. The notification claimed that the EPA had reason to believe that Consumers disposed of PCBs and arranged for the disposal and treatment of PCB-containing materials at portions of the site. In 2011, Consumers received a follow-up letter from the EPA requesting that Consumers agree to participate in a removal action plan along with several other companies for an area of lower Portage Creek, which is connected to the Kalamazoo River. All parties asked to participate in the removal action plan, including Consumers, declined to accept liability. Until further information is received from the EPA, Consumers is unable to estimate a range of potential liability for cleanup of the river. Based on its experience, Consumers estimates its share of the total liability for known CERCLA sites to be between $3 million and $8 million. Various factors, including the number and creditworthiness of potentially responsible parties involved with each site, affect Consumers’ share of the total liability. At September 30, 2025, Consumers had a recorded liability of $3 million for its share of the total liability at these sites, the minimum amount in the range of its estimated probable CERCLA liability, as no amount in the range was considered a better estimate than any other amount. The timing of payments related to Consumers’ remediation and other response activities at its CERCLA and NREPA sites is uncertain. Consumers periodically reviews these cost estimates. A change in the underlying assumptions, such as an increase in the number of sites, different remediation techniques, the nature and extent of contamination, and legal and regulatory requirements, could affect its estimates of NREPA and CERCLA liability. Ludington Overhaul Contract Dispute: Consumers and DTE Electric, co-owners of Ludington, entered into a 2010 engineering, procurement, and construction agreement with Toshiba International, under which Toshiba International contracted to perform a major overhaul and upgrade of Ludington. Toshiba International later assigned the contract and all of its obligations to TAES. TAES’ work under the contract was incomplete, defective, and non‑conforming. Consumers and DTE Electric repeatedly documented TAES’ failure to perform under the contract and demanded that TAES provide a comprehensive plan to resolve those matters, including adherence to its warranty commitments and other contractual obligations. Consumers and DTE Electric engaged in extensive efforts to resolve these issues with TAES, including a formal demand to TAES’ parent, Toshiba, under a parent guaranty it provided. TAES did not provide a comprehensive plan or otherwise meet its performance obligations. As a result of TAES’ defaults, Consumers and DTE Electric terminated the contract. In order to enforce their rights under the contract and parent guaranty, and to pursue appropriate damages, Consumers and DTE Electric filed a complaint against TAES and Toshiba in the U.S. District Court for the Eastern District of Michigan in 2022. TAES and Toshiba filed a motion to dismiss the complaint, along with an answer and counterclaims seeking approximately $15 million in damages related to payments allegedly owed under the parties’ contract. As a co-owner of Ludington, Consumers would be liable for 51 percent of any such damages, if liability and damages were proven. The court denied the motion to dismiss filed by TAES and Toshiba. The trial is scheduled to begin in the fourth quarter of 2025. Consumers believes the counterclaims filed by TAES and Toshiba are without merit, but cannot predict the financial impact or outcome of this matter. An unfavorable outcome could have a material adverse effect on CMS Energy’s and Consumers’ financial condition, results of operations, or liquidity. In 2023, Toshiba announced that TBJH became the majority shareholder and new parent company of Toshiba through a common stock purchase. TBJH is a subsidiary of a Japanese private equity firm. Consumers and DTE Electric continue to monitor this development, but do not believe that this affects their rights under the parent guaranty provided by Toshiba. In 2023, the MPSC approved Consumers’ and DTE Electric’s jointly-filed request for authority to defer as a regulatory asset the costs associated with repairing or replacing the defective work performed by TAES while the litigation with TAES and Toshiba moves forward. Although litigation is ongoing, Consumers currently estimates that its share of repair, replacement, and other damages resulting from TAES’ defective work is approximately $350 million, which may be offset in part or entirely by any potential future litigation proceeds received from TAES or Toshiba. Consumers and DTE Electric will have the opportunity to seek appropriate recovery and ratemaking treatment for amounts recorded as a regulatory asset following resolution of the litigation, including any amounts not recovered from TAES or Toshiba. Consumers cannot predict the financial impact or outcome of such proceedings. Consumers Gas Utility Contingencies Consumers expects to incur remediation and other response activity costs at a number of sites under NREPA. These sites include 23 former MGP facilities. Consumers operated the facilities on these sites for some part of their operating lives. For some of these sites, Consumers has no present ownership interest or may own only a portion of the original site. At September 30, 2025, Consumers had a recorded liability of $60 million for its remaining obligations for these sites. Consumers expects to pay the following amounts for remediation and other response activity costs during the remainder of 2025 and in each of the next five years:
In Millions
| 2025 | 2026 | 2027 | 2028 | 2029 | 2030
Remediation and other response activity costs |  | $ | — |  |  | $ | 3 |  |  | $ | 8 |  |  | $ | 25 |  |  | $ | 11 |  |  | $ | 3 |
Consumers periodically reviews these cost estimates. Any significant change in the underlying assumptions, such as an increase in the number of sites, changes in remediation techniques, or legal and regulatory requirements, could affect Consumers’ estimates of annual response activity costs and the MGP liability. Pursuant to orders issued by the MPSC, Consumers defers its MGP-related remediation costs and recovers them from its customers over a ten-year period. At September 30, 2025, Consumers had a regulatory asset of $85 million related to the MGP sites. Guarantees Presented in the following table are CMS Energy’s and Consumers’ guarantees at September 30, 2025:
In Millions
Guarantee Description | Issue Date | Expiration Date | Maximum Obligation | Carrying Amount
CMS Energy, including Consumers |  |  |  |  |  |
Indemnity obligations from sale of membership interests in VIEs 1 | various | various |  | $ | 229 |  |  | $ | — |
Indemnity obligations from stock and asset sale agreements 2 | various | indefinite |  | 152 |  |  | — |
Guarantee 3 | 2011 | indefinite |  | 30 |  |  | — |
Consumers |  |  |  |  |  |
Guarantee 3 | 2011 | indefinite |  | $ | 30 |  |  | $ | — |
1 These obligations arose from the sale of membership interests in Aviator Wind, Newport Solar Holdings, and NWO Holdco to tax equity investors. NorthStar Clean Energy provided certain indemnity obligations that protect the tax equity investors against losses incurred as a result of breaches of representations and warranties under the associated limited liability company agreements. These obligations are generally capped at an amount equal to the tax equity investor’s capital contributions plus a specified return, less any distributions and tax benefits it receives, in connection with its membership interest. For any indemnity obligations related to Aviator Wind, NorthStar Clean Energy would recover 49 percent of any amounts paid to the tax equity investor from the other owner of Aviator Wind Equity Holdings. Additionally, Aviator Wind holds insurance coverage that would partially protect against losses incurred as a result of certain failures to qualify for production tax credits. For further details on NorthStar Clean Energy’s ownership interest in Aviator Wind, Newport Solar Holdings, and NWO Holdco, see Note 11, Variable Interest Entities. 2 These obligations arose from stock and asset sale agreements under which CMS Energy or a subsidiary of CMS Energy indemnified the purchaser for losses resulting from various matters, including claims related to taxes. The maximum obligation amount is mostly related to an Equatorial Guinea tax claim. 3 This obligation comprises a guarantee provided by Consumers to the U.S. Department of Energy in connection with a settlement agreement regarding damages resulting from the department’s failure to accept spent nuclear fuel from nuclear power plants formerly owned by Consumers. Additionally, in the normal course of business, CMS Energy, Consumers, and certain other subsidiaries of CMS Energy have entered into various agreements containing tax and other indemnity provisions for which they are unable to estimate the maximum potential obligation. CMS Energy and Consumers consider the likelihood that they would be required to perform or incur substantial losses related to these indemnities and those disclosed in the table to be remote. Other Contingencies In addition to the matters disclosed in this Note and Note 1, Regulatory Matters, there are certain other lawsuits and administrative proceedings before various courts and governmental agencies, as well as unasserted claims that may result in such proceedings, arising in the ordinary course of business to which CMS Energy, Consumers, and certain other subsidiaries of CMS Energy are parties. These other lawsuits, proceedings, and unasserted claims may involve personal injury, property damage, contracts, environmental matters, federal and state taxes, rates, licensing, employment, and other matters. Certain of these matters, while potentially substantial, are covered by insurance and the insurer or insurers are involved in the relevant proceedings. Further, CMS Energy and Consumers occasionally self-report certain regulatory non‑compliance matters that may or may not eventually result in administrative proceedings. CMS Energy and Consumers believe that the outcome of any one of these proceedings and potential claims will not have a material negative effect on their consolidated results of operations, financial condition, or liquidity.

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