Can a provisional patent application be filed within the 1 year grace period for after public disclosure, or does it need to be a non-provisional application?
To obtain a patent for an invention, it should pass through various toll gates such as a)Novelty b)Obviousness c)Enablement d)subject matter and e)Industrial application.
In order to overcome the novelty criteria, the invention should be new.It should not be available in the public domain prior to filing for a patent.Such law relating to novelty is enforced in India and Europe.The patent law in India and Europe states that an invention should be anticipated by a prior art prior to its filing in any form.
Few exceptions are provided in the Indian Patent Act under which the patent application can be filed despite public disclosure, and such public disclosure will not be considered to have been anticipated.However, the patent application should be filed within twelve months from such disclosure.
Anticipation by previous publication (Sec. 29)
Anticipation by previous communication to the government (Sec. 30)
Anticipation by public display (Sec. 31)
Anticipation by public working (Sec. 32)
Anticipation by use and publication after provisional specification (Sec. 33)
The law is different in USPTO,there is a grace period of 1 year within which one can file a patent application(provisional or non provisional) even after the invention is made available in the public domain.Americans Inventors act (AIA) 35 U.S.C. 102(b)(1)(A) provides that a disclosure which would otherwise qualify as prior art under AIA 35 U.S.C. 102(a)(1) is not prior art if the disclosure was made: (1) One year or less before the effective filing date of the claimed invention; and (2) by the inventor or a joint inventor, or by another who obtained the subject matter directly or indirectly from the inventor or joint inventor.
Either a provisional or a non-provisional application can be used. But remember, any application is only as good as what it contains. If you take "provisional" to be "very sparse on depth and breadth" then it may not do the job. But it isn't the difference between provisional and non provisional, it is the difference between a complete discourse and a poor disclosure.
See http://www.legalzoom.com/patents-faq/when-file-provisional-application-patent.html which appears to disagree. I think they're wrong, though.