Conversion de-duplication is the process of attributing a sale or lead to a single CPA online marketing channel or campaign for payment. It enables the merchant to pay only one single source of trafic and prevents paying many times for the same sale.
Usually, conversion de-duplication is made by firing only one third party conversion tag on the confirmation page. It requires complex tag management and good tracking capabilities within ads and links displayed by marketing partners.
The most often, de-duplication is made on a "last cookie" or "last referrer" basis, but it can also use more complex set of rules.
Strictly speaking, conversion de-duplication is distinct from conversion attribution. The first is to decide which partner to pay for a conversion and the latter is to estimate how each partner has contributed to the conversion.
In an ideal world, conversion retributions or sales commissions should be aligned against attribution model results, but it never occurs. From a practical point of view, it is hard to share commissions between partners for each multi-touch sale and some partners (PPC platforms) have to be paid before a possible conversion. Moreover, it may be difficult to discuss conditional tagging with some powerful partners.
Therefore, "First click affiliates" who are often the best conversion contributors are the most often victims of conversion de-duplication against "last click affiliates", PPC search engine platforms and retargeting networks.
As fair de-duplication is hard to achieve, de-duplication can provoke partner and affiliate backlash. To limit these drawbacks, merchants must have clear and transparent de-duplication policies.
Examples of deduplication policies:
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