New Year Present From China - Compulsory XML Patent Filing In China From 1 January 2026

On 20 May 2025, the CNIPA announced that from 1 October 2025, all electronic patent filings have to be done in XML format, including any subsequently filed amendments. Otherwise, the subsequently filed PPH request, and request to delay examination will be denied. (https://www.cnipa.gov.cn/art/2025/5/26/art_75_199841.html)

On 12 November 2025, the CNIPA further announced that from 1 January 2026, the CNIPA will not accept any electronic filings that are not in XML format. (https://www.cnipa.gov.cn/art/2025/11/12/art_75_202551.html)

Specifically, XML filing should be used for filing all application documents including specification for invention patent, utility model, and design patent application, request for re-examination or invalidation, and all responses and observations. The only exception is nucleic or amino acid sequence in WIPO ST.26 format.

My personal views are in italic below.

What are the problems?

The major problem is that it is very difficult for the user (most of the time a patent attorney and their colleagues) of the patent electronic filing system to ascertain the contents of the XML submission received at the patent office, exposing the user to huge risk of mishandling as XML in the US and China is considered as the original disclosure (This is a lot better for PCT national phase entry into China, as the originally filed PCT application is considered as the original disclosure instead. This now further strengthen the reason when foreign filings into China should go through PCT), because it is known that a XML file will look differently on different computers.

On the other hand, it is unclear what are the advantages to anyone filing patent applications in XML format. If the advantage is to have files of smaller size so that the patent office could spend less in data storage, this is certainly not true. With assistance of Large Language Model in conjunction with modern search engines, there does not seem to have any advantage to facilitate or accelerate searching with categorization of the different sections in a patent specification by tagging (I will not use an AI tool for patent work if the tool could not distinguish various portions of a patent specification). On the otherhand, to avoid risks of mishandling, the user has to use much more resources to handle a patent filing, so it is even more expensive for the entire system. Personally, I do not see any gains in increased efficiency, higher data quality (See below that this may in fact result in lower quality, or no quality at all for failed filings), smarter interface, improved application quality (Seriously, the quality of a patent application could be improved by the way of filing the application?), ease of use, and compatibility said by the USPTO (see https://www.uspto.gov/patents/docx). These will be clear from the discussion below. However, I will be grateful for any enlightenment on the advantages of using XML for filing patent applications to the patent offices (I do not see any advantage to patent practitioner and the applicant as of now).

What has happened in the US?

For comparison, the situation in the US is described below. The information in this article regarding the US side is kindly provided by Ms. Kasie Grover of Schwegman Lundberg & Woessner, P.A.

The USPTO has tried to "force" XML filings since 17 January 2024 by requiring additional fees of USD400 for non-XML filings. However, the USPTO still allows uploading a backup (auxiliary) PDF version of an application with the corresponding DOCX version, in particular after the happening of several filing errors.

My understanding is that the DOCX version is submitted to the USPTO, and the USPTO then carries out the conversion of this to XML.

For US practitioners, the major problem is that it cannot be ascertained what would come out in the XML document after conversion at the USPTO, particularly for patent specifications containing mathematical formulae, symbols (like ≥, δ), and chemical structures and formulae. There have been many cases that the XML document after conversion contains "monstrous" texts instead of the original intended texts.

What is happening in China?

By contrast to the US system, China does the below:

• From 1 October 2025, for non-XML filings, subsequent filing of PPH request and request delay examination will be denied. (It is interesting to see that the CNIPA does not allow acceleration and deceleration of examination for non-XML filings – you just sit tight and do not move.)
• After 1 January 2026, in fact all patent electronic filings must be done in XML format.
• China does not accept any legal effect of the filing of backup (auxiliary) PDF version of an application as a fallback.
• China requires the XML conversion to be done at the user end, for example at a Chinese patent firm. The burden on the user side is even higher in China, as the user could view the PDF preview of the XML submission before filing – there is no excuse that the error was not caused by the user.

In China, as the conversion is done at the user end, the CNIPA has warned the users the following:

• There are specific settings in the DOCX document used for conversion for XML submission, including font, font size, margin, no extra blank lines, and so on, that should be observed.
• Special characters (like symbols), mathematical formulae, chemical structures/formulae, complex tables (i.e. tables with merged cells) should be converted to pictures to be embedded in the DOCX document.
• The picture must be in TIFF format, which is not a very efficient picture format with respect to size. (I found that the picture format WEBP is a much more efficient format, even better than JPG or PNG, although more efficient for color pictures than black and white pictures. However, as WEBP is from Google, the CNIPA may not like this format......)

As fellow readers know, many patent specifications do not contain only texts, but also many different ways to describe an invention, which is necessary as an invention is supposed to be something that has not existed in the world before filing – we need new ways to describe a new thing. All of these restrictions in fact are diminishing the freedom of expression. (Well, this is China, which should be expected.)

Interestingly, there are commercial software in China that could solve all of these conversion problems. (I am 200% certain that none of the people selling such software is from or have connection with the CNIPA.)

This is a real case that happened to me personally. I filed a patent specification having 150+ pages with many chemical structures and formulae. My colleagues and I struggled for five days to try to convert the specification into XML format for submission, where in-between we received many error messages from the CNIPA submission software, having no idea what went wrong. Finally, we used a commercial software to do the conversion, and the specification went through. However, the application could not be submitted to the CNIPA, as the CNIPA has a 60MB size limitation, and the converted XML file is 192MB. Eventually we had to file in paper, and told the CNIPA this incident, hopefully the applicant could still file PPH or delay examination acceptable to the CNIPA. I was recently told by the CNIPA that we should reduce the size of the pictures in the specification (Sure, let's do this one-by-one over the weekend). However, we did not want to do this as such reduction may make the pictures blurry. (As mentioned above, all of the XML submission I did have XML files larger than the corresponding PDF files, and therefore there is no saving in data size as far as I am concerned.)

What is the solution?

The main reason why PDF is the preferred version for review and submission is that the PDF is kind of "fixed". Although a PDF could be edited, typically this is not easily done without a trace. Therefore, what typically happens is like below:

• The specification is reviewed by the inventor, and with approval from the inventor, the patent attorney generates the PDF version for a final review by the inventor to approve for submission.
• The PDF specification with approval from the inventor is filed by the patent attorney, with the help of their colleagues.

In between, there is a high degree of certainty that the PDF document is not changed, not even how it looks from one computer to another, and all the people involved know exactly what is being passed from one person to another. XML does not have this certainty.

Therefore, the solution is simple – let us file in PDF (or whatever format that we have certainty of what we are filing) and make this our original disclosure, and we are happy to give you patent offices the DOCX version of the specification where the PDF is from. You want to convert the DOCX to XML version or do whatever the hell, be my guest, as long as the converted file is not the original disclosure.

I was told that the WIPO is also going to "encourage" XML filings, and hope that the above could be considered.

As always, any thoughts and/or comments are welcomed.

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