Clear Clipboard on OS X after 'n' seconds
The script below clears the clipboard every S seconds:

#!/bin/sh
# pbclear [seconds]

S=${1:-10}

while true
do
    pbcopy &lt; /dev/null
    sleep $S
done


Save it to a file named pbclear, set executable permissions with chmod +x pbclear, and put it somewhere in your path, for instance, /usr/local/bin. Then run it in the background with  pbclear 60 &amp; to clear the clipboard every 60 seconds.