He claimed that the script was used in late first millennium and that he had only rediscovered it, but no text from before the 18th century has been discovered.

[4][5] The Limbu or Sirijunga script was devised during the period of Buddhist expansion in Sikkim in the early 18th century when Limbuwan still constituted part of Sikkimese territory.

The Limbu script is an abugida, which means that a basic letter represents both a consonant and an inherent, or default, vowel.

Long vowels without a following final consonant are written with a diacritic called kemphreng ⟨᤺⟩, for example, ⟨ᤁ᤺⟩, /kɔː/.

ᤕᤛᤗᤠᤀᤡ᤺ ᤀᤃᤠᤍᤡ ᤒᤎᤠᤀᤢᤏᤠᤁᤠ ᤗᤠᤃᤡ ᤁᤠᤶᤋᤡᤔᤠ ᥈ ᤛᤠᤕᤠ ᤗᤧᤰ ᤗᤡᤶᤒᤢ ᤓᤠᤙᤠᤔᤠ ᤜᤢᤏᤠ ᤈᤠᤖᤥᤖᤣ ᤇᤠ। ᤋᤩᤛᤁᤠᤖᤏ ᤗᤡᤶᤒᤢ ᤓᤠᤙᤠᤔᤠ ᤗᤧᤂᤠᤜᤠᤖᤢ ᤗᤧᤰᤏᤠ ᤛᤢᤖᤢᤃᤠᤷᤏᤠ ᤛᤠᤒᤤ ᤗᤡᤶᤒᤢᤓᤠᤙᤡ ᤔᤡᤳᤖᤜᤠᤖᤢᤔᤠ ᤜᤠᤷᤍᤡᤰ ᤀᤠᤏᤢᤖᤨᤎ ᤇᤠ। Three additional letters were used in early versions of the modern script:[2] Two ligatures were used for Nepali consonant conjuncts:[6] Nineteenth-century texts used a small anusvara (ᤲ) to mark nasalization.

Limbu script was added to the Unicode Standard in April, 2003 with the release of version 4.0.