Supplemental Segment information	12 Months Ended
Dec. 31, 2025
Supplemental Segment information
Supplemental Segment information	Note 15—Supplemental Segment information Our Chief Executive Officer serves as our chief operating decision maker (“CODM”) and assesses performance for and allocates resources for our single contract drilling services segment based on our consolidated net income or loss, as presented on our consolidated statements of operations. The significant segment expense categories regularly provided to our CODM include our operating and maintenance costs and our general and administrative costs, as presented on our consolidated statements of operations. Other segment items included in our consolidated net income or loss include depreciation and amortization, loss on impairment of assets, gain or loss on disposal of assets, interest expense and income tax expense or benefit. Additionally, our CODM reviews our segment assets, as presented on our consolidated balance sheets. Our CODM uses our consolidated results of operations to evaluate income or loss generated from segment assets, or return on assets, to make decisions to deploy cash flows from operations for reinvestment in our contract drilling services segment or for other uses, such as for acquisitions, debt and equity investments, liability management or to pay dividends to our shareholders. Consolidated results of operations are used to monitor actual results relative to historical, budgeted and forecasted results and to assess segment performance against our peers.

Supplemental Segment information

12 Months Ended

Dec. 31, 2025

Note 15—Supplemental Segment information

Our Chief Executive Officer serves as our chief operating decision maker (“CODM”) and assesses performance for and allocates resources for our single contract drilling services segment based on our consolidated net income or loss, as presented on our consolidated statements of operations. The significant segment expense categories regularly provided to our CODM include our operating and maintenance costs and our general and administrative costs, as presented on our consolidated statements of operations. Other segment items included in our consolidated net income or loss include depreciation and amortization, loss on impairment of assets, gain or loss on disposal of assets, interest expense and income tax expense or benefit. Additionally, our CODM reviews our segment assets, as presented on our consolidated balance sheets.

Our CODM uses our consolidated results of operations to evaluate income or loss generated from segment assets, or return on assets, to make decisions to deploy cash flows from operations for reinvestment in our contract drilling services segment or for other uses, such as for acquisitions, debt and equity investments, liability management or to pay dividends to our shareholders. Consolidated results of operations are used to monitor actual results relative to historical, budgeted and forecasted results and to assess segment performance against our peers.

- Definition

The entire disclosure for reporting segments including data and tables. Reportable segments include those that meet any of the following quantitative thresholds a) it's reported revenue, including sales to external customers and intersegment sales or transfers is 10 percent or more of the combined revenue, internal and external, of all operating segments b) the absolute amount of its reported profit or loss is 10 percent or more of the greater, in absolute amount of 1) the combined reported profit of all operating segments that did not report a loss or 2) the combined reported loss of all operating segments that did report a loss c) its assets are 10 percent or more of the combined assets of all operating segments.

+ References

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+ Details

Transocean Ltd. 10-K