In Jain tradition, “Kumar” is normally a personal name (first or middle name), not a gotra.

• Jain gotras are things like Goyal, Bansal, Kothari, Kasliwal, Shah, Choradia, etc. (depending on the Jain community – Agarwal, Oswal, Khandelwal, Porwad, etc.).
• So when you see a name like “Ashok Kumar Jain”, the gotra is something else, not “Kumar”.
• Because of this, there is no specific “Kumar gotra caste” in Jain samaj in the traditional sense.

If in your area people are informally using “Kumar” as a gotra, that would be a local/social usage, not a standard Jain gotra defined in Jain Dharma. For exact family details, it is best to confirm from your elders, family records, or community register, as Jain scriptures themselves do not list “Kumar” as a gotra.