shares of oscar health inc rose about 25 to 447 in tuesday premarket trading after the company named mark bertolini the former chief executive of health insurance giant aetna inc as its next chief executive oscar healths stock was up about 46 on the year as of mondays close mr bertolini will take the post effective april 3 the company said he will succeed mario schlosser who cofounded oscar in 2012 with joshua kushner mr schlosser will take the new title of president of technology reporting to mr bertolini oscar health also reaffirmed its 2023 guidance as outlined in its fourthquarter earnings report on feb 9