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EXHIBIT 99.1 PTransocean TRANSOCEAN LTD . REPORTS SECOND QUARTER 2021 RESULTS • Total contract drilling revenues were $ 656 million ( total adjusted contract drilling revenues of $ 713 million ) , compared with $ 653 million in the first quarter of 2021 ( total adjusted contract drilling revenues of $ 709 million ) ; • Revenue efficiency ( 1 ) was 98.0 % , compared with 97.4 % in the prior quarter ; • Operating and maintenance expense was $ 434 million , compared with $ 435 million in the prior period ; • Net loss attributable to controlling interest was $ 103 million , $ 0.17 per diluted share , compared with net loss attributable to controlling interest of $ 99 million , $ 0.16 per diluted share , in the first quarter of 2021 ; • Adjusted EBITDA was $ 255 million , compared with adjusted EBITDA of $ 245 million in the prior quarter ; and . Contract backlog was $ 7.3 billion as of the July 2021 Fleet Status Report . STEINHAUSEN , Switzerland — August 2 , 2021 — Transocean Ltd. ( NYSE : RIG ) today reported a net loss attributable to controlling interest of $ 103 million , $ 0.17 per diluted share , for the three months ended June 30 , 2021 . Second quarter 2021 results included net favorable item of $ 6 million , or $ 0.1 per diluted share , related to discrete tax items . After consideration of this net favorable item , second quarter 2021 adjusted net loss was $ 109 million , $ 0.18 per diluted share , compared to $ 117 million adjusted net loss , $ 0.19 per diluted share , in the first quarter of 2021 . Contract drilling revenues for the three months ended June 30 , 2021 increased sequentially by $ 3 million to $ 656 million , primarily due to three rigs that returned to work following a shipyard stay , partially offset by two rigs that went idle in the second quarter . A non - cash revenue reduction of $ 57 million was recognized in the second quarter as a result of contract intangible amortization associated with the Songa and Ocean Rig acquisitions . This compares with $ 56 million in the prior quarter . Operating and maintenance expense was $ 434 million , compared with $ 435 million in the prior quarter . General and administrative expense was $ 39 million , in line with the first quarter of 2021 . Interest expense , net of amounts capitalized , was $ 115 million , in line with the first quarter of 2021. Interest income was $ 4 million , compared with $ 3 million in the previous quarter . The Effective Tax Rate ( 2 ) was ( 4.6 ) % , down from 17.8 % in the prior quarter . The decrease was primarily due to higher earnings in jurisdictions with lower tax rates , releases of uncertain tax positions related to settlements and other various discrete items . The Effective Tax Rate excluding discrete items was ( 10.2 ) % compared to ( 5.7 ) % in previous quarter .