De-duplication best practice

What is de-duplication? The process ensuring that two different affiliates aren’t awarded for the same sale or when an advertiser chooses not to pay for a sale if the affiliate channel was not the last referring marketing channel.

Dual Networks:

Where an advertiser has an affiliate program on two networks, de-duplication is essential to prevent paying commission for the same sale twice. This can occur when a customer has visited different affiliates who are working across different networks, so both networks would record the click and conversion. 


Using automatic de-duplication or "conditional tracking" is the best method to prevent this from occurring. This is done by appending a parameter to the merchant’s clickthrough URL (click append) when sending a visitor to any page on the merchant’s website. For example: ‘source=commissionfactory’. The parameter and value is recognised by the merchant’s site and is used to trigger the writing of a local cookie which stores the source of the visitor. The source could be Commission Factory or any other advertising channel that the merchant wishes to de-dupe against.  Subsequently, if the customer is sent back to the merchant by one of the other advertising channels then the local cookie should be overwritten with one for the last referring advertising channel. ​The advertiser only displays the conversion tracking code for the network that had the last click in the customer journey. Therefore, only one network receives the notification of the sale, thus removing the need to decline duplicate sales manually at the validations stage. We have some specific code examples on how this can be implemented, but how this is done will depend on your tracking is implemented. Some shopping carts have more limited functionality than others, so please ask your developer to review.


Advertiser A added a click append to their URL for each online channel to define where the customer had arrived from, for example:

They then wrote a script to place a local cookie on the user’s computer triggered by the presence of the click append.

They then established a rule that the click append source ID would be overwritten on a last referrer basis.

For a customer clicking through via a Rakuten publisher who then browses and returns via a Commission Factory publisher the source id “?source=rakuten” would be replaced with “?sourceid=commissionfactory”.

The tracking tag logic at the sale confirmation page would recognise the “?sourceid=commissionfactory” click append and show only the Commission Factory tracking code, thus correctly awarding the sale to the last referring network.

All traffic must be tagged to ensure accurate cross-channel de-duplication. The last referrer wins method must be used cross all channels to ensure fair de-duping.

If automated de-duplication is not possible, then this can be done via validation process, however it will be more time consuming for the advertiser to manage and also to manage in bound support queries around why orders are voided.

Which online channels should advertisers de-duplicate against?

Do not de-duplicate against organic search/direct traffic: these are typically non paid channels and along with brand paid search will often be the last visit in a user’s journey. It's important to be respective of the channel and your partners.

Communication with publishers

Your de-duplication policy must be clearly communicated with your publishers. This can be added to the program description page. If you are live and implement a new policy around this, then we also recommend outlining the policy via a message to all your publishers via the message centre.