Based on my experience with Sinar digital backs, which spit out a raw, bias, dark and flat frame all independently, I think most cameras include this calibratio

Based on my experience with Sinar digital backs, which spit out a raw, bias, dark and flat frame all independently, I think most cameras include this calibration hardcoded into the raw, because otherwise it is extremely easy to see! I know Phase One backs have calibrations that compensate for this, column errors, and hot pixels in their IIQ raws by default.