Yes "over here" is Mexico.
Country of origin rules have many loopholes. Like the percentage of value added or the substantial transformation, since Mexico has no refining capabilities an oil that is blended an bottled in Mexico form components refined in the US could be marked as "Made in USA" because the more substantial transformation occurred in the United States. Or the value added in Mexico is less than the value added in the US.
Quote:
Substantial Transformation
The traditional substantial transformation rule states that a good originates in the last country where it emerged from a given process with a "distinctive name, character or use." The substantial transformation of a good requires more than just a change in the article -- it requires an article be transformed into a "new and different article" "having a distinctive name, character or use."
Substantial transformation captures the purpose of origin determination in a simple, concise manner: a good is a product of the country where it last underwent substantial transformation.
Value-Added Percentage Test
The value-added test defines the degree of transformation required to confer origin on the good in terms of a minimum percentage of value that must come from the originating country or a maximum amount of value that can come from the use of imported parts and materials. If the percentage does not fall within the accepted range, the last production process will not confer origin. If the determination is for non- preferential purposes, origin will be conferred on a prior country; if it is for preferential purposes, no further origin determination is necessary unless the prior county is also a beneficiary country under a preferential trading agreement with the importing county.
The value-added test can generate substantial compliance costs for companies. Further, it can generate substantial uncertainty because the test ignores exchange rate risk and fluctuations in the price of raw materials, the possible daily changes in status of goods as the currency values or price of raw materials fluctuate, and so forth.