If we ask not about traditional dates, but about the earliest independent / external evidence for Kundakunda, scholars usually look at inscriptions and securely dated later texts.

In brief:

1. Mercara Copper-plate Inscription (Saka 388 = 466 CE)

- This plate mentions the “anvaya (lineage) of Kundakunda” and names several teachers in his line. - If taken at face value, this would be the earliest known inscriptional (external) reference to Kundakunda. ( jainworld.jainworld.com) - However, later epigraphic study has shown that this plate is probably an 8th–9th‑century forgery, so its historical value is disputed. Because of this, many scholars no longer treat it as solid evidence for a 5th‑century reference.

1. Inscriptions of the “Kundakund‑anvaya” in Karnataka (from 797 CE)

- Early epigraphical records of the Jain sect called Kundakund‑anvaya are found in Karnataka (old Mysore region) and are securely dated from 797 CE onward. ( jainqq.org) - These inscriptions speak of the lineage/sect tracing itself to Kundakunda (often with sub‑divisions like Deśiga‑gana etc.). - They are generally accepted as the earliest reliable inscriptional evidence for a tradition linked to Kundakunda, even though they emphasize the lineage more than biographical details of the Āchārya himself.

1. Later literary references (10th–12th century)

- Digambara authors like Devasena (10th c.) and Jayasena (12th c.) explicitly refer to Kundakunda and also use the name Padmanandin for him. ( jainheritagecentres.com) - These are among the earliest securely dated textual references to Kundakunda in the surviving Digambara literature.

So, in terms of earliest external reference:

• If the Mercara copper plate is accepted as genuine:

→ Earliest known mention is that Saka 388 (466 CE) inscription referring to Kundakunda‑anvaya.

• If we follow the now-dominant scholarly view that the plate is a later forgery:

→ The oldest reliable external evidence is the group of Karnataka inscriptions from 797 CE onward mentioning the Kundakund‑anvaya sect; → Direct, clearly dated literary references to Kundakunda by later ācāryas come from about the 10th–12th centuries.

For a simple overview of Kundakunda’s place within the Digambara tradition and his main works, you can read more here