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Marketable securities (Tables) | 6 Months Ended
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Jun. 30, 2021
Marketable Securities [Abstract] |
Marketable securities held | The below table shows the carrying value of our investments in marketable securities for periods presented in this report.
(In $ millions) |  | As at June 30, 2021 |  | As at December 31, 2020 |
Archer |  | 13 |  |  | 8 |  |
Total marketable securities |  | 13 |  |  | 8 |  |
Gains and losses related to marketable securities | The below table shows the gain and losses recognized through net loss for the periods presented in this report.
(In $ millions) |  |  |  |  |  | Six months ended June 30, 2021 |  | Six months ended June 30, 2020
Seadrill Partners - Common units - unrealized loss on marketable securities |  |  |  |  |  | — |  |  | (2) |
Archer - unrealized gain / (loss) on marketable securities |  |  |  |  |  | 5 |  |  | (4) |
Total unrealized gain / (loss) on marketable securities |  |  |  |  |  | 5 |  |  | (6) |

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- Definition Tabular disclosure of marketable securities. This may consist of investments in certain debt and equity securities, short-term investments and other assets. + References No definition available. + Details
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