David Schwartz

David Schwartz.

David Schwartz is an American software engineer and cryptographer, one of the three original architects of the XRP Ledger. As of 28 August 2026, Ripple lists him as a board member, while its 2026 event material uses the title CTO emeritus. He is no longer the company's operating chief technology officer.

XRP Ledger

In 2011, Schwartz, Jed McCaleb and Arthur Britto began developing the system that became the XRP Ledger. The ledger launched in June 2012. After the launch, the founders transferred 80 billion of the 100 billion created XRP to the company then called NewCoin and soon renamed OpenCoin. Schwartz served as OpenCoin's chief cryptography officer.

Career at Ripple

Schwartz later became Ripple's chief technology officer in July 2018. In September 2025 he announced that he would step back from daily duties at the end of that year, become CTO emeritus and join Ripple's board. Ripple's current leadership page lists him only in the board section; Dennis Jarosch took responsibility for technical operations.

Earlier technical work

Before the XRP Ledger, Schwartz worked on distributed computing and other software systems. A 1988 patent application credited to David J. Schwartz and assigned to David Schwartz Enterprises described a multilevel system for distributing parts of a computing task; U.S. patent 5,025,369 was granted in 1991. He also publishes code under the handle JoelKatz.

Consensus work

Schwartz co-authored the 2014 paper The Ripple Protocol Consensus Algorithm with Noah Youngs and Arthur Britto. It described an early form of the protocol using overlapping sets of trusted validators. The hosted paper now carries a warning that it does not represent the current ledger protocol and directs readers to a 2018 analysis for updated safety and liveness conditions.

In the current design, each server chooses validators it trusts not to collude, commonly described as a Unique Node List. Validators exchange proposals about transactions for the next ledger version; a server validates a result when the required overlap and agreement thresholds are met. If agreement cannot be reached, the design favors stopping progress over confirming divergent ledger histories.

The distinction between the historical paper and the evolving protocol is important when describing Schwartz's work. He was an original designer and published an influential early explanation, but present network behavior is defined by deployed open-source software, validator configuration and later protocol research rather than by that paper alone.

Public technical activity

The verified JoelKatz GitHub profile links Schwartz to public repositories and technical experiments. It is useful evidence for the pseudonym and his public development activity, but individual repository ownership should not be interpreted as proof that he alone created every component of the XRP Ledger.

Ripple, XRP and the XRP Ledger

Ripple is a company; the XRP Ledger is an open-source network; XRP is the ledger's native asset. Schwartz's role in designing the ledger does not mean that he alone controls the network, and his current Ripple board position should not be confused with his former executive post.