A marketplaces and communities case study

How Poshmark reduced spam and created a secure online community


Poshmark is the largest social commerce marketplace for fashion, where anyone can buy, sell and share their personal style. With over 3 million Seller Stylists and millions of shoppers, Poshmark strives to keep an open and trusted environment for their community.


Reduction in spam content

More frictionless environments for valued users

Told from the perspective of

Robbie Fritts,Director, Fraud and Payments
“Our partnership with Sift Science has really allowed us to focus on growth and enable our community to have a secure and trusted environment where they can share their personal style.”


  • Social marketplace for fashion
  • 3 million Seller Stylists on the platform


  • Community and trust are key to the brand
  • Need to mitigate spam content and fraudulent transactions
  • Aim to maintain a frictionless experience for trusted users


  • Increased conversions and better experiences for legitimate shoppers
  • ML models quickly adapted to Poshmark’s unique marketplace needs


  • 60-70% reduction in spam content
  • Secure and trusted online community

A network of trust

Online businesses face a variety of fraud and abuse threats. With over 12,000 sites on our platform, we collect, analyze, and learn from 100s of millions of events every day. Let’s fight fraud together.