Need for the Certificate of Origin
Why would you need a Certificate of Origin? Apart from being a document that proves that a product was produced and at one point modified, remember that not all countries have the same governmental rules and regulations.
Keep in mind that all countries will require a certificate to be filled out and that Commercial invoices usually supply a statement of origin but most authorities will make you furnish a separate document for validating origin.
Nations that participate in the Free Trade Agreement might have preferential exceptions. This type of exclusive document borrows its' name from preference.
If you are seeking a COO why not have your documents prepared adequately for you foreign purposes and uses? Also a specific Certificate of Origin exists for certain countries and was made for commerce among countries that participate in a Free Trade Agreement.