I don’t see a seal on this document.
A standalone paper unattached to any document means nothing. Likewise a simple easily duplicated stamp or printing also proves nothing. It is only a stamping created by an engraved and not easily forge-able instrument that will suffice.
This is why kings of old had signet rings. They made a wax impression of their ring to seal documents to vouch for their authenticity. A document without a stamped engraved seal was worthless.
Likewise even today a document without a stamped or embossed seal is worthless for the same reason.
Unfortunately, in today's world even embossing tools are easily forged. Printing alone is even more forge-able even when using colored inks.
There are some special purpose inks which may appear to change color when viewed from different angles such as some of the inks used in modern U.S. paper bills but even those inks are available if one can afford to pay the price for obtaining forbidden items.
The point of mentioning the lack of an embossed seal on Obama’s ‘birth certificate’ was to attest that there was no seal on the document and any other document alluding to the validity of another document other than itself is worthless unless both documents are physically inseparable.
Once the two documents became parted, there is no longer any guarantee of the validity of the document being vouched for. Only an embossed irremovable seal or irremovable and incontestable marking can guarantee the validity of any document.