Enforcement Rules of Value-added and Non-value-added Business Tax Act Article 9

The term "small business entity" as used in the Act means a business entity of a small-scale with sporadic transactions, the monthly sales amount of which does not reach the threshold for using uniform invoices.
中文原文 加值型及非加值型營業稅法施行細則第9條
本法稱小規模營業人,指規模狹小,交易零星,每月銷售額未達使用統一發票標準之營業人。

English translation for reference only; the Chinese text prevails. Not legal advice.