Patents not on

Hi, my name is Art, Prior Art.
I’m the guy all of you are looking for!

Ok, my name is really Russ but I’ve always wanted to use that line but I haven’t found myself in a situation where it would be appropriate (or for that matter understood!).

I mentioned the fact that the modern fractional patents are not online to the patent office in 2008 but as of the last time I checked they have not been made available at In fact, the patent office has only done one of the many things I’ve suggested! (To be fair it is one more suggestion than google patents has implemented!)

Prior Art be darned, the patents listed on this page are not available online at

Modern Fractional Patents

These modern fractional patents are on microfilm produced by the uspto. I made copies when I found myself at the Public Search Facility in Alexandria, VA. Scans and ocr results are available at these links:

  1. 2,712,152 ½
  2. 3,262,144 ½

Here is a page that discusses modern fractional patents and contains links to modern fractional patents that are online.

Fractions in Patent Numbers at

A page used to exist on that explained how trailing letters were added to represent the fractional component of patent numbers that needed them. A copy of that page is here.

Reissued Patents

While working on my reissued patents page for this site I noticed that these are not online at so I added them here:

  1. RE1
  2. RE2
  3. RE4
  4. RE6
  5. RE8
  6. RE9
  7. RE11
  8. RE12
  9. RE15
  10. RE18
  11. RE23
  12. RE26
  13. RE28
  14. RE31
  15. RE37
  16. RE38
  17. RE43
  18. RE44
  19. RE48
  20. RE50
  21. RE52
  22. RE56
  23. RE57
  24. RE70
  25. RE71
  26. RE75
  27. RE78
  28. RE83
  29. RE112
  30. RE116

Press the search button below to issue a search on the uspto’s site for these reissued patents. The patents do not have classifications or pdf files (click the Images button of each page).

X Patents

These much, much older X patents are on the USAPat dvd’s the uspto produced but they are not online at The images on the USAPat dvds were converted to pdf’s and the contents were ocr’ed and made available right here:

  1. X999
  2. X1334
  3. X3262
  4. X3342
  5. X4583 (this one is actually online now but wasn’t when I wrote this)
  6. X4898
  7. X4973
  8. X6105
  9. X7326

Here is a page of mine that explains X and fractional X patents with links to the ~2,000 that are online at

There is even more information in this article, cited as requested:

Hampton, Barbara J. (2021) “Stalking the Wild X Patent,” Journal of the Patent and Trademark Resource Center Association: Vol. 31, Article 4.
Available at: