SIP-158: Deprecate Inverse Synths


Simple Summary

This SIP proposes to deprecate inverse synths in favour of the shorting mechanism introduced in SIP 103. Once this SIP is implemented and iSynths are removed from the protocol a planned upgrade of Multi-collateral shorts will allow for more assets to be added to the shorting mechanism.


This SIP will remove inverse synths from the protocol by pausing exchanging into all inverse Synths then deprecating them for future redemption via the SynthRedeemer contract introduced in SIP-174.


With the introduction of shorting in Multi-collateral loans SIP-103 the ability to open natural shorts on ETH and BTC was introduced without using iETH or iBTC.

The ongoing management of iSynths requires manual intervention by the pDAO to purge all holders and reset them each time they freeze. The design of the inverse synths pricing also introduced leverage as they reached their upper / lower limits, which required exchange fees to be increased to deal with frontrunning.

Upgrades to the multi-collateral loan and shorts contracts on L1 will enable shorting on a wider range of assets, starting with the top ten traded Synths by volume.



Technical Specification

  1. Pause exchanges on all iSynths.
  2. Remove iSynths from the Synthetix (deprecating them), remove aggregators from exchangeRates contract, resume any synths that are suspended (allowing them to be transferable again)

Test Cases

Configurable Values


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