🔰 Final Standard

PIP-49: Validator Delegation

Authors	Pactus Development Team [[email protected]]
Discussion	View Discussion PIP-49
Category	Core
Created	2026-03-08

Abstract
Motivation
Specification
Reward distribution
Backward compatibility

Abstract #

This PIP proposes a validator delegation mechanism that allows a stake owner to authorize another party to operate a validator on their behalf. In return, block rewards are split between the validator operator and the stake owner based on a predefined share.

Motivation #

Currently, only the stake owner can run a validator. Some users may not have the technical capability or infrastructure to operate validator nodes, while still wanting to participate in staking.

This proposal enables stake owners to delegate validator operations to an operator and receive a configurable portion of rewards without running validator infrastructure themselves.

Specification #

This proposal introduces two explicit roles:

Stake Owner: the account that owns the bonded stake.
Validator Operator: the key/entity that runs validator duties.

Validator structure #

The Pactus validator data structure is extended with an optional delegation section.

type validatorData struct {
  PublicKey           *bls.PublicKey
  Number              int32
  Stake               amount.Amount
  LastBondingHeight   uint32
  UnbondingHeight     uint32
  LastSortitionHeight uint32

  // Optional delegation fields.
  DelegateOwner  crypto.Address // Stake owner account address
  DelegateShare  int64          // Owner share in nano PAC (portion of 1.0 PAC block reward)
  DelegateExpiry uint32         // Block height at which delegation expires
}

If delegation fields are absent, the validator is treated as non-delegated.

Bond transaction #

The bond transaction includes optional delegation fields. If provided, the resulting validator is considered delegated and must satisfy all delegation validation rules (share bounds, expiry validity, and owner address presence).

Unbond transaction #

For delegated validators, only the stake owner can submit an unbond transaction.

Withdraw transaction #

Only the stake owner can receive principal stake in withdrawal transactions.

Reward distribution #

DelegateShare defines the stake owner’s reward share and MUST be within [0, 0.7 PAC], represented in nano PAC (10^9 units per PAC).

The total block reward remains 1.0 PAC and is distributed as:

Protocol share: 0.3 PAC
Stake owner share: DelegateShare
Validator operator share: 0.7 PAC - DelegateShare

The three outputs MUST sum to exactly 1.0 PAC.

Backward compatibility #

To activate this proposal, the protocol block version is increased to 3 once more than 75% of the committee’s total power supports the upgrade.