In Farnum v. Buffum, 58 Mass. 260 (1849) a Rhode Island notary public took an acknowledgment but did not affix an official seal authenticating his act.
The statute involved provided:
[Deeds of real estate may be acknowledged] before any justice of the peace in this state, or before any justice of the peace, magistrate or notary public, within the United States, or in any foreign country.
The court upheld the acknowledgment as good:
The statute requires no notarial seal to the notary's certificate of acknowledgment, and none, we think, was necessary. The notary derived his authority from the statute, and it is not a good objection to the validity of the certificate, that by the common law or the law merchant, notaries public are required to certify their acts and doings under their notarial seals. Hinckley v. O'Farrell, 4 Blackf. 185, Dumont v. McCracken, 6 Blackf. 355. (Emphasis added).
However, G.L.c. 233, §73, which was enacted after the decision in Farnum, provides:
All oaths and affidavits administered or taken by a notary public, duly commissioned and qualified by authority of any other state or government, within the jurisdiction for which he is commissioned and certified under his official seal, shall be as effectual in this commonwealth as if administered or taken and certified by a justice of the peace therein.
So, although under the Farnum decision a seal is not necessary in the case of an out-of-state acknowledgment, the affixing of a seal in the case of such an acknowledgment will serve to validate the acknowledgment and raise a presumption as to its authenticity.
Interestingly enough, REBA's Title Standard No. 16 up until the year 2000 seemed, based on the decision in Ashkenazy v. R. M. Bradley & Co., 328 Mass. 242, 103 N.E.2d 251, to require a seal on out-of-state acknowledgements notwithstanding the decision in Farnum. But that was changed in that year, and the Title Standard now provides as follows: "An acknowledgement taken in another state before a notary public without a notarial seal or stamp impressed or affixed to the instrument and without any certificate of authority is not on that account defective."