Prasit Patumphadungsak, a parliamentary candidate for Pathum Thani from the Prachachon Party, posted exposing that ballot papers may not be confidential and could likely have unique running numbers that reveal who voted for whom.
On 13 Feb 2026 GMT+7, Prasit Patumphadungsak, Pathum Thani parliamentary candidate for the Prachachon Party, posted about district-based ballot papers where officials mistakenly tore ballots that showed the booklet and ballot numbers, stating:
For example, booklet number B0719961 contains 20 ballots. Calculated as 0719961 x 20 = 14,399,220.
Therefore, this booklet includes ballot numbers from 14,399,201 to 14,399,220, and this particular ballot bears the number B14399212, which is highly likely to be a unique running number.
Prasit further explained that the green ballots might also reveal who voted for whom. Each booklet number like B0719961 contains 20 ballots numbered B14399201 to B14399220, with this ballot numbered B14399212 accordingly.
The ballot includes the voter's sequence number, which is the ID of each person at that voting station; for example, his own is 396. If that number is found, it identifies him, 'Mike Prasit,' as the source. Each ballot also has a QR Code that can be scanned—such as EH1RQ—which is likely another unique number.
"I tried to decode EH1RQ to 14399212 but haven't succeeded yet (anyone who can, please inform me). However, cracking this code may not be necessary if we already have a database mapping EH1RQ to 14399212, allowing identification of the ballot owner and their vote choice."
Prasit additionally posted a hypothetical scenario using Chat GPT:
1. Generate sets of 5-character numbers and letters starting from 00001 up to 99999, then A0000, A00001 up to ZZZZZ, totaling 60,466,176 codes, which exceeds the 52 million registered voters (adjustable to fit exact numbers).
2. Randomly shuffle these codes and map them in a database to ballot numbers from B00000001 to B52000000 (assuming printing 52 million ballots).
3. After the election, to identify who cast a particular ballot, scan the QR Code to get EH1RQ, input it into the program, and it will map back to the original voter, instantly revealing who voted for whom.