As you know PPA's are not examined, so of course, neither are they ever rejected if they are filed in the wrong classification (say it should have gone in "Lasers", and somehow "households" was used). In fact it is never even published. For this reason that error may never be caught until the non-provisional is drafted ... or maybe not even until much later when the non-provisional is challenged.

Since that is the case, then considering a non-provisional patent (it having the correct classification) issuing from the PPA ... can it still claim the date of the PPA even though the PPA was filed in the wrong classification?

Similarly, if there are other non-critical discrepancies unrelated to the actual invention or claims (for example, an inventor residence missing or wrong), does that affect the strength of the PPA if that information is correct in the non-provisional? How about if an inventor is added or changes between the PPA vs the non-provisional?

Any answer (including wild guesses) will be most appreciated.

2 Answers 2


DISCLAIMER: This is not legal advice, and is not to be relied upon for legal decisions. I am not attorney. Read the relevent laws yourself and consult with an attorney.


The classification noted on a patent application is only a suggestion to the USPTO made in good faith (i.e. you could get in trouble for intentionally trying to mislead/etc) - it is not necessarily the final classification: see the ADS Instructions Document (ADS form is the same for PPA and non-provisional):

Enter a suggested classification for the application. Optional.

The requirements for claiming benefit of the filing date of a PPA are described in the MPEP here and the requirements for a provisional application are here - classification isn't mentioned. That doesn't mean it couldn't be buried somewhere else. However, knowing that the purpose of the PPA is to fully disclose the invention that will be filed for non-provisionally, it seems like the classification of the PPA is less important.

Finally, sometimes multiple patent applications can claim benefit to the same PPA (or previous non-provisional application). I know of no requirement that they be the same classification, which would seem strange as it is easily conceivable that the same disclosure could give rise to applications in different classifications. Indeed, most patents are cross-classified in multiple classes and subclasses. I am sure that if one cared to look, they could find examples of applications that claimed benefit to applications in a different classification. Furthermore, the many 'interestingly classified' issued patents and applications are somewhat of a laughing stock in the patent community.

That being said, if you could amend the ADS to update the suggested classification (don't remember rules for that off-hand), one would think it would probably be better and may help avoid accusations of inequitable conduct during later infringement lititgation.


See MPEP 602 (37 CFR 1.41(c)):

Once a cover sheet as prescribed by § 1.51(c)(1) is filed in a provisional application, any correction of inventorship must be pursuant to § 1.48.


An application must include, or be amended to include, the name of the inventor for any invention claimed in the application (the inventorship).

That being said, sometimes you can have the situation where a provisional application has one set of inventors, and a non-provisional application is only partially reliant on the provisional - and so may have a different set of inventors. If this is not the case, though, the provisional application's inventors may need to be corrected.


MPEP 602 again:

Each inventor’s residence must be included on the cover sheet for a provisional application unless it is included in an application data sheet (37 CFR 1.76).

If only a mailing address where the inventor customarily receives mail is provided, the Office will presume that the inventor’s residence is the city and either state or foreign country of the mailing address. If the inventor lives at a location which different from the inventor’s mailing address, the inventor’s residence (city and either state or foreign country) must be included in the inventor’s oath or declaration or an application data sheet.

Again, you may need to update the ADS...So...

Updating the ADS:

MPEP 601 (37 CFR 1.76(c)):

Information in a previously submitted application data sheet, inventor's oath or declaration under § 1.63, § 1.64 or § 1.67, or otherwise of record, may be corrected or updated until payment of the issue fee by a new application data sheet providing corrected or updated information, except that inventorship changes must comply with the requirements of § 1.48, foreign priority and domestic benefit information changes must comply with §§ 1.55 and 1.78, and correspondence address changes are governed by § 1.33(a).

Hope this helps!

  • This helps a lot. I also noticed that it said that all you need is one name in common between the PPA and non-provisional, for example if multiple new names are added to the non-provisional. It seems a lot of the means for correcting errors in the provisional is largely for the sake of the inventors ... it really doesn't seem to make a difference as long as the information is correct in the non-provisional. PPA's are a lot more flexible than I thought. I guess that's how people get away with craming a lot of different inventions into one PPA. Nov 5, 2015 at 23:38

Proper classification is the responsibility of the USPTO, and not the applicant.

Non-provisional applications are relatively often misclassified, and this is not something that can cause any challenge to the validity of a filing date or the enabling nature of the disclosure. It may cause less than adequate proficiency in examination, but that is another matter.

Provisional applications are not classified.

The other situations you mention will rarely jeopardize the enabling status of a provisional application, if caused by unintentional error. However, if there has been an incorrect declaration of inventorship with malicious intent, this could cause a complete loss of the filing status.

  • Thank you. The provisionals online do require a classification ... but I'm guessing, based on your input that it doesn't mean anything. I guess that makes sense since they are not published that the classification doesn't mean anything. Nov 5, 2015 at 20:39

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