Roger E. Markwell has been granted 30 US patents while listed as an inventor at Beecham Group Plc. The first was granted in 1982 and the most recent in May 2009. Roger E. Markwell ranks #121,623 of 4,157,543 US inventors in our database (top 2.9%). Patent records list Roger E. Markwell in Great Dunmow, PA, GB.