According CLDR definition, below locales follow standard-decimal #,##,##0.### which has two different grouping sizes, but java looks cannot correctly return the secondary grouping size
·as· ·bn· ·brx· ·ccp· ·dz· ·en_IN· ·gu· ·hi· ·kok· ·ks· ·ml· ·mr· ·or· ·pa· ·ta· ·te·

For example:
input data:123456789
Expected result on en_IN should be 12,34,56,789, according to CLDR definition: https://www.unicode.org/reports/tr35/tr35-numbers.html#Number_Format_Patterns
Actually: 123,456,789