Surveying, Mapping and GIS

The Pennsylvania registration law states the following:

§ 37.58. Seal. (a) A registrant shall obtain, at the registrant’s own expense, a seal in the design authorized by the Board. The following are Board authorized seals for ‘‘Registered Professional Engineer’’ (Design A), ‘‘Registered Professional Land Surveyor’’ (Design B) and ‘‘Registered Professional Geologist’’ (Design C):

(b) The seal shall contain the legend ‘‘Registered Professional Engineer,’’ ‘‘Registered Professional Land Surveyor’’ or ‘‘Registered Professional Geologist’’ and the registrant’s name and registration number.
(c) The seal shall be 1 3/4 inch in diameter. The diameter of a pocket seal may be reduced to 1 1/2 inch if the design is in the same relative proportions in subsection (a).
(d) A registrant may use a rubber stamp or computer image which is a facsimile of the seal, if the registrant first obtains a seal in accordance with this section.

§ 37.59. Use of seal. The following rules govern the proper use of a registrant’s seal:
(1) A registrant may use his seal and signature only when the work being sealed and signed was prepared by the registrant or under the registrant’s complete direction and control.
(2) When a registrant issues final or complete documents to a client for the client’s records, or when a registrant submits final or complete documents to public or governmental agencies for final review, the seal and signature of the registrant who prepared or who directed and controlled the preparation of the documents, along with the date of issuance, shall be prominently displayed on the first page of all documents. Facsimile seals shall appear on all subsequent pages of plans or plats.
(3) When multiple registrants prepare or direct and control the preparation of documents, each registrant’s seal and signature shall appear on the first page of the documents, or on the first page of the identifiable portion or section of the documents which were prepared or directed and controlled by that registrant, if the respective registrants’ direction and control can be reasonably segregated.
(4) When a registrant’s signature is applied, it shall be applied near or across the seal, but not in a location that obliterates the registration number.
(5) A registrant may not affix or permit a seal and signature to be affixed to a document after the expiration of the registrant’s licensure status, or for the purpose of aiding or abetting another person to evade or attempt to evade a provision of the act or this chapter.
(6) In the case of a temporary permit issued to an engineering, land surveying or geology registrant of another state, the registrant shall use the seal of the registrant’s home state and shall affix his signature and a copy of the temporary permit to work performed in this Commonwealth.

http://www.pacode.com/secure/data/049/chapter37/chap37toc.html

The issue here is that with electronic seals, once the drawing is transmitted to another party with the seal affixed, it becomes easy to lose control over the drawing. Should the drawing be modified, there still may be potential liability isses which may come and find the original surveyor, right, wrong or indifferent. The Pennsylvania Registration Law allows it, however with the implication that proper safeguards be utilized. Currently CAD technology doesn't allow much control over this type of digital sealing. Of course the expectation is also that the drawing should be signed, near or across the seal.

As for me, I still prefer the old-fashioned way- "wet seals". I typically include a note in the title block "this drawing not valid without original seal and signature". Additionally I usually apply a seal using ink in a contrasting color from the print, such as blue ink on blackline, or vice-versa... I usually also sign across the seal similarly in a contrasting color.

Until CAD software can accomodate digital seals and signatures, which can "self-destruct" if the drawing is modified or tampered with, I tend to think better safe than sorry...