1. A method for identifying intended input to a digitizer sensor, the method comprising: identifying a plurality of regions of input to a digitizer sensor over a plurality of refresh cycles; classifying each of the plurality of regions as one of intended input and unintended input, wherein the classifying is performed for each of the plurality of refresh cycles and is based on at least one of size and shape of the regions; storing a list of locations of regions classified as unintended input regions, wherein each entry of the list is stored for a pre-defined time period and then subsequently removed from storage; and invalidating output obtained from a region classified as a region of intended input, responsive to the region at least partially overlapping a location already listed in the list of locations of the regions classified as unintended input regions.