Independent Bank (IBCP) had the highest return between January 1, 2011 and February 28, 2011 by a US stock with a market cap of $500M+, returning 203.1%.
Perspective Therapeutics (CATX) had the highest return between January 1, 2014 and April 30, 2014 by a US stock with a market cap of $500M+, returning 391.8%.