Retargeting, also known as  remarketing is proving to be the new exciting phenomenon in internet advertising. Basic retargeting started out with placing the cookie in user’s browser and following and targeting the user in the network of sites. Today with various service providers like Google, DSPs (demand side platforms) and other retargeting service providers available with different technology, cookie pools and segmentation, retargeting can offer marketers excellent return on investment.

Real-time bidding (RTB) provides flexible advertising opportunities for targeting. As an example, take a set of users (tracked as a 'cookie pool') which went up to payment gateway (let’s call it SET 1), and you have another set which visited your site but did not "add to cart"(and call this SET 2). Now you may want to push your promotions to SET 1 in a more aggressive manner at one point, while running a 2-day promotional campaign across the network. This is just one situation – if you hold dynamic data – you may like to target users on time, on specific site/placement on site, specific parameter (propensity to consume) and so on.

To illustrate it further, now you can target users who visited your site and performed different actions with a different creative, at different times and with different landing pages. You can also target cookie pools of other sites (by buying pools) with similar user behaviour which you expect to convert on your website. This can be done effectively for e-commerce, classifieds and content portals. Retargeting works best for portals seeking an action like transaction or lead by targeting cookie pools at different stages of taking action. The different stages on an e-commerce site are tracked as a navigation waterfall (or funnels) in the following manner:

Homepage –> Product Detail page -> Add to cart -> Check-out page -> Payment success

Various advertisers, researches and what retargeting companies are claiming that:

1. Retargeted inventory performs 2x(minimum claims) better in terms of conversion rates over normal inventory
2. 20% of browsers give 50% of transactions, with comScore claiming 18% of browsers giving 80% of clicks. This makes retargeting that much more important and with real-time bidding – dynamic creatives and landing pages(as per targeting parameters).
3. Retargeting effectiveness rises with the base of the website and the base of retargeting service provider

In addition to the cookie pools you have from your sites, there are cookie pools available in the market. Buying/using cookie pools from the market may be worthwhile, depending on the yield on the same.

However, there are complications from a publishers perspective, because retargeting, audience measurement and ad-serving companies can take away cookie information without (or with having hidden norms in the contract) your knowledge, and sell the cookie pools in the market. Publishers should be very careful before signing any contracts that data collected in terms of both cookies(or even surveys) cannot be shared with a third party.

Display advertising can change a great deal, with growth in retargeting. With big display platforms allowing retargeting, the CPMs can be dynamic and in all probability be much higher than regular display CPMs. The sell-thrus may be a concern but overall value creation is much higher. With Samsung sites having close to 5 million Unique Visitors (UVs), Nokia having 2.5 million UVs, and Suzuki, Honda and Hyundai sites having 0.5 million UVs each(as per comScore) – retargeting can help big brands reach out to definite prospects in a targeted manner. 

From a users perspective, retargeting can offer both value and nuisance. For example if you searched for air ticket rates for "Delhi to Mumbai" on one travel site, and then you see banners of "Delhi to Mumbai" on other sites from same travel site, and you might feel unnerved, wondering about how they got to know that you have to go Mumbai. I took some user feedback on this, and it was mostly negative, and most people did not like the fact that their travel information was known to firms and they were being targeted on that basis. When I asked them about e-commerce targeting, they were more receptive to the fact that it can act as a reminder to buy something which they had left half way.