Miles & Stockbridge, a Baltimore firm that dates to 1932, has become the largest law firm based in Maryland, according to the National Law Journal. About two years ago, Miles & Stockbridge opened an office at the UM BioPark just a few blocks from its headquarters to house its fledgling biotechnology practice. ‘‘That was done to better understand the business,” said chairman John Frisch. ‘‘Our attorneys meet with scientists and others in those companies on a daily basis."