Startup Directory


Mark Ayzenshtat ’04CC and Josh McFarland both left Google to found TellApart. The TellApart Data Platform helps clients collect & organize the most precious and predictive information they have access to: their own customer data.

Basic display ad retargeting has been around for 13+ years, yet many early vendors have not updated their technology.  TellApart sets out to completely revolutionize the practice of retargeting using the latest in cloud-based data storage, predictive analytics, real-time media buying and personalized, dynamic ad serving techniques.

Retargeting is the process of showing display ads to potential buyers who visited but abandoned their shopping activity on e-commerce websites.  95%+ of visitors are not buying. TellApart Transactional Retargeting helps bring them back through the use of dynamic, personalized banner ads which show the right products to the right visitors.  Simply put, it turns lost shoppers into return customers.

Mr. Ayzenshtat is both a co-founder and the CTO of TellApart. Previously, he was an Entrepreneur in Residence at Greylock Partners. Prior to this, Mr. Ayzenshtat was a Senior Software Engineer for four years at Google, where he started and led several high profile projects including the Android Market, the AdWords API, and natural language processing improvements within the core Search Quality team. Android later won the Founders’ Award, Google’s most prestigious project honor.