UPDATE: Late Thursday night, Halliburton released a six-page response to the National Oil Commission’s findings. You can read the full release here.

The Fred Bartlit-led legal team investigating the causes of the Deepwater Horizon oil spill on Thursday released a bombshell finding: that despite multiple test results showing that a cement-foam mixture meant to seal the bottom of the well was unstable, Halliburton and BP used the flawed material anyway.