The absorption principle, also called roll-up, is a rule-of-origin mechanic: once an intermediate material has itself qualified as originating under the applicable rule, its full value is treated as originating when the next stage of production is assessed, and the non-originating inputs that went into making it are not counted again against the finished product. It matters most under value thresholds, where counting the same non-originating content twice would sink an otherwise qualifying product. No official page defining the term could be found, and it would be wrong to imply one exists. Whether absorption is available, and how it works, depends on the particular origin protocol — and on keeping the supplier declarations that establish the intermediate’s origin.
Why this entry carries no source list. The concept generalises; the definition does not. What this term means for your shipment is set by the particular trade agreement’s own text — its origin protocol, its annexes, its tariff schedules — and two agreements can use the same word differently. There is no central authority to cite, and citing one agreement would imply a generality that does not exist. The operative document is the one governing your trade, and it is what a customs authority will read.