Common Securitization Solutions (CSS) was founded in 2013 as a joint venture between Fannie Mae and Freddie Mac to standardize mortgage securitization across the two government-sponsored enterprises. Its core product, the Common Securitization Platform (CSP), is a cloud-native system that handles the issuance and administration of mortgage-backed securities, connecting the secondary mortgage market to investors.
The scale at which the CSP operates is significant: it supports issuance and administration of 71% of all mortgage-backed securities in the United States, processing trillions of dollars in securities. In 2023, CSS completed a major architectural milestone by implementing an Active/Active deployment across multiple AWS regions, with a claimed zero data loss outcome - a meaningful resiliency standard for infrastructure of this criticality.
From a technical standpoint, the platform sits at the intersection of distributed systems engineering, high-availability architecture, and financial services infrastructure. The engineering challenges span multi-region AWS deployments, fault-tolerant system design, and the operational demands of market infrastructure that underpins a substantial portion of U.S. housing finance. The company describes itself as the largest and most technologically advanced mortgage securitization administrator in the financial services industry.
CSS occupies an unusual position in the fintech landscape: a purpose-built, mission-driven entity owned by two of the largest participants in the U.S. mortgage market, yet operating as a technology platform provider focused on transparency, liquidity, and standardization across the secondary mortgage market.
