Patent Reexamination Numbers and PatFT, part II

In a previous post, I asked:

The USPTO PatFT page for Patent Number Search lists three examples for reexamination patent numbering:

Re-examination — RX29,194 RE29183 RE00125

However, if you type in those three “example” numbers into the search box, you get a “PN/RX29,194: 0 patents” error and two reissue patents.  It is odd that the USPTO examples aren’t valid…

Anyone know of a valid re-examination number (for a project I’m working on)?

Mike Brown, in a comment, noted that “I was recently working on a re-examination, and needed to find examples. The easiest way is to search by serial number – use the “90? series for ex-parte re-examinations, and “95? series for inter-partes. For example:  APN/90005727 is an ex-parte case, APN/95000050 is an inter-partes.”

However, it still didn’t answer the exact question I had.  So, for my project…I dug deeper.

Once a reexamination has been concluded, the Patent Office issues a “Certificate of Reexamination” that denotes how the issued patent was corrected by the reexamination.  That “Certificate of Reexam.” is then attached to the original patent’s images (but not full text) on the USPTO site.  Example:  USPN 5,108,388.

Frustratingly, I still ask two questions:

1.  Why does the PatFT give examples for reexaminations that are either null (RX29,194) or are for reissues (RE29183, RE00125)?

2.  What is a valid reissue [reexamination] number (for use on PatFT or even PAIR)?  Is the PatFT page in error for listing examples?  Is there another way to search?

Some example reexamination numbers…in case one of you can figure it out (from the “U.S. Patent Number Guide” generated by Michael White):

  • Ex Parte Reexamination #1 relates to USPN 4,104,156
  • Ex Parte Reexamination #7864 relates to USPN 5,343,123
  • Inter Parte Reexamination #1 relates to USPN 6,232,427
  • Inter Parte Reexamination #118 relates to USPN 6,696,316

Perhaps I should just ask Mr. White…

Update.  Mr. White replied to me, noting that:

I have no idea what these so-called “example” re-examination numbers are. They are definitely not reexamination numbers. As far as I know, there is no way to search reexamination application serial numbers in PatFT. Reexamination certificates are not OCRed or indexed. (A standing complaint among professional patent searchers.) Their numbers are not searchable in the APN field. You can only retrieve them by retrieving the patent document to which they’re attached. Obviously, the person who put together these “helpful” examples was not familiar with PTO documents or data. (Probably a contractor.)

However, rexam serial numbers are searchable in Public/Private PAIR using the format “90nnnnnn” for ex parte and “95nnnnnn” for inter partes. There appear to be PAIR records for ex partes back to the mid 1980s but file wrapper documents are only available from ~2003 forward.

3 thoughts on “Patent Reexamination Numbers and PatFT, part II”

  1. > 1. Why does the PatFT give examples for
    > reexaminations that are either null (RX29,194)
    > or are for reissues (RE29183, RE00125)?

    I’d guess it’s because the people who made up the examples didn’t understand the difference between reissues and reexamination. RX29194 wouldn’t even be possible, since it would be a reissue of an “X” series patent, and there were less than 10,000 of them.

    > 2. What is a valid reissue number (for use on
    > PatFT or even PAIR)?

    RE39258 is a valid reissue number.

    > Is there another way to search?

    You can see all of the reissues just by using PN/RE0$ through PN/RE4$ (the highest number appears to be RE40622 at the moment)

    To answer your original question, I don’t think reexaminations HAVE numbers, as such. Reissued patents do, but they’re considered new patents (at least, a new issue of a patent). A reexamined patent is still the original patent.

  2. When writing reexaminations, I wated to find examples of successful and unsuccessful requests. So, I took a look at the Official Gazette Notices site ( ), chose cases from maybe 6 months to 2 years in the past and looked up the file wrapper in Public Pair. Although, for the last request I wrote, I swtiched to the standard format for obviousness rejections “Reference A discloses ___, but fails to disclose ____. However, reference B teaches___. It would have been obvious….since (motivation)”.

Leave a Reply

Your email address will not be published. Required fields are marked *

You may use these HTML tags and attributes: <a href="" title=""> <abbr title=""> <acronym title=""> <b> <blockquote cite=""> <cite> <code> <del datetime=""> <em> <i> <q cite=""> <strike> <strong>