I have a long digit number about 12 digits long and I have the Scientific Notation option un-checked so it looks like a 12 digit number, but as soon as I try to copy it from the data grid, it automatically transforms to a Scientific Notation number. Thus when I paste the number into any editor, it will paste as a Scientific Notation number.
This does not happen in Toad for Oracle 10.6.1.
Click the cell only once to prevent the cell to go into Edit mode.
Click on a different cell and arrow to number cell so it will not go into Edit mode. Then press CTRL + C to copy the data, it will still copy the data as a long number and not in Scientific Notation.
Waiting for fix to be released in a future version of Toad for Oracle.