https://www.epo.org/en/searching-for-patents/helpful-resources/asian/chinese-taipei/numbering-system

Numbering system - Chinese Taipei (TW)

Numbering system - Chinese Taipei (TW)

Document types and kind codes

GONGKAI (A)	公開	unexamined patent publication (>2003)
GONGGAO HEZHUN	公告核准	examined patent publication (<2004) examined utility model publication (<2004)
GONGGAO FAZHENG (B/U)	公告發證	granted patent publication (>2004) registered utility model publication (>2004)

Number formats

(y)yy t nnnnn application numbers	two digits for the Republican year* (y) one digit for the type of right (t) five digits for the serial number (n) * Conversion rule for Republican years: Republican year + 1911 = Western year (example: Republican year 98 = 2009) Note: from 2011 (= Republican year 100) onwards, the year part in the application numbers will comprise three digits.
yyyy nnnnn unexamined publication numbers	four digits for the Western year (y) five digits for the serial number (n)
nnnnnn examined publication numbers	six digits for the serial number (n)
t nnnnnn grant numbers	one digit for the type of right (t) six digits for the serial number (n)

Types of patent right (t)

application numbers:
1 - invention patent
2 - utility model
3 - design

grant numbers:
I - invention patent
M - utility model
D - design