ACUとは累積の事です
詳しい解説はFTA/EPAにおける累積のページで解説を
行っております。
ACUは”ACCUMULATION”の略となります。
以下に日タイFTA/EPAの協定文の累積の部分を記載します。
Article 29
Accumulation
For the purposes of determining whether a good qualifies as an
originating good of a Party,
an originating good of the other Party which is used as a material
in the production of the good in the former Party may be
considered as an originating material of the former Party.
日本語訳は以下になります。