from multi-factor authentication (mfa) to risk-based authentication: duo’s historyfounded in 2010 by dug song and jon oberheide, duo security began as a secure access company focused on multi-factor authentication (mfa) that was dedicated to being kinder than necessary and building for the future. we expanded beyond our ann arbor, michigan, beginnings in 2015 to meet the increased, international need of over 2,000 customers. no matter how much we grew, we never stopped placing customer experience and customer trust first, expanding our data security offerings beyond mfa with tools that were easy, effective and enduring.