We're currently implementing a voucher system on our site which will allow our users to obtain a 25+% discount on certain products, provided they donate 10% of the purchase price to charity.

We will offer the ability to share the discounts via social media in return for larger discounts to the sharer for each person who clicks through the link and buys an item.

I understand that social links have SEO benifits, but this appears to be based on lots of people sharing the same link. If our voucher users share a unique link i.e. http://ourdomain.com/sipsfesdf rather than a fixed link http://ourdomain.com/product-name will we still receive the same benifts?

Should we instead share something like http://ourdomain.com/product-name/sipsfesdf

Thanks in advance.