Lab Name

Private Data Objects

Short Description

The Private Data Objects lab provides technology for confidentiality-preserving, off-chain smart contracts.

A private data object (PDO) is a stateful “smart contract” that implements a set of access and update policies on confidential data shared between individuals or organizations. The contract defines a set of message handlers that act on the state of the contract; handlers can modify state, perform some computation over the state, and/or generate messages for other objects.

Preservation of the integrity of contract execution and the enforcement of confidentiality guarantees come through the use of a trusted execution environment (TEE). While the approach will work with any TEE that guarantees integrity and confidentiality for code and data, our current implementation uses Intel@ Software Guard Extensions (SGX).

Private data objects leverage the existence of a distributed ledger to ensure serialization of contract commits and to enforce dependencies between the commits. Initially, we will implement the “Commit and Coordination Log” as a HL Sawtooth transaction family. Our future plans include implementations for other ledger platforms.

Scope of Lab

This project provides two substantial advances for Hyperledger distributed ledger platforms. First, it provides a ledger-independent, off-chain smart contract service that preserves participant, state, and contract confidentiality. Second, the connection to existing ledgers comes in the form of a commit and coordination log (CCL). This allows off-chain contracts to coordinate commits without exposing details of the contract. The CCL is similar conceptually to existing proposals for a “Global Synchronization Log”.

Initial Committers

  • andmiele1 (
  • bvavala (
  • byron-marohn (
  • cmickeyb (
  • EugeneYYY (
  • harmonh (
  • TomBarnes (


Dan Middleton (

Pre-existing repository

Existing repository is internal to Intel. We plan to transfer to Hyperledger github upon receiving required HL and Intel internal approvals.