Chip Pearson wrote:
Adam,

Once the spreadsheet is put into tangible form (such as simply
saving it to disk), you already have copyright (not copywrite)
protection. The advantage of registering it with the US Copyright
Office is that this is a requirement to sue someone for
infringement. (You can register it after infringement occurs, but
you must register it to get in to court.).

Excel is a product of Microsoft, covered by copyright protection.
Spreadsheets created with Excel are not.


Although it may be advantageous to register a copyright with the United
States, that is not a requirement for suing someone for copyright
infringement. Failing to register might in some cases limit the damages
that can be recovered for infringement that occurred prior to the
commencement of the suit.

Alan Beban