Fix normalization of USPTO document numbers for granted patents

[amotl]

@aghster spotted an issue with normalizing numbers for USPTO appropriately:

I think you will have to pad document numbers for granted patents with leading zeros to ensure that the length is 8 for patents preceeding US 10,000,000 B2. However, normalize_patent_us() does not seem to do this.

See also [the kind of reference implementation] PatentsViewApp.openPDF().

[amotl]

Dear @aghster,

thank you so much for watching this closely enough so you have been able to spot this. Shortly after deploying this release, we already recognized spurious exceptions like ValueError: US document number "US2548918" has unexpected length.

You are right, https://github.com/ip-tools/ip-navigator/blob/5f4ec85edbdd6090003aaf87962384693c3ae3ec/patzilla/util/numbers/normalize.py#L390 apparently does not account for padding to 8 digits yet - happy to see you linked to the reference implementation already.

We will try to improve that, thanks again.

Cheers,
Andreas.

[amotl]

@aghster: Should be fixed through f8c4d50 and will become part of the next release.

[amotl]

We can confirm this should be fixed now. You might want to partly validate the outcome by having a look at the corresponding doctests:

• Source https://github.com/ip-tools/ip-navigator/blob/8b9256af7eb1677e98e62ab890f1b6f09e90cb52/patzilla/access/uspto/pdf.py#L52-L65

• Proof

  • https://patzilla.ip-tools.io/api/pdf/US2548918

Thanks again for spotting this, @aghster!