In the United Kingdom, Shuttleworths are lists of people canvassed to be likely to vote for a particular political party in the PIG model of an electoral campaign. The idea is that once someone is determined to have voted, they are crossed off the list, thus maintaining an always up-to-date record of voters who have not yet been out to vote. They are usually printed on carbon paper so that the Shuttleworth may be reused.
"Shuttleworth" is the proprietary Liberal Democrat name for the scheme. Now largely superseded by EARS for the Lib Dems, Bluechip for the Tories and Contact Creator for the Labour Party.