SHARKSTAR®HT high temperature, filtration control additive is a special modified starch derivative used to reduce filtration in most water-based drilling fluids including fresh water, seawater and saturated brine up to 300°F. It is designed to replace SHARKSTAR® in applications with the BHT>250°F. SHARKSTAR®HT will encapsulate drill cuttings and exposed wellbore formations to reduce particle dispersion and reactive shale formation swelling. Subject to bacterial degradation, a biocide is recommended to prevent fermentation in fluids which are not salt saturated.