New BSIP: Added disable_modify_max_supply flag

[xeroc]

BSIP: TBD
Title: Flag to prevent issuer from modifying asset max_supply
Authors: Blockchain Projects BV
Status: Draft
Type: Protocol
Created: 2019-02-22
Discussion: https://github.com/bitshares/bitshares-core/pull/1612

Abstract

The proposed change adds another flag and permission to assets that, when toggled, will prevent the issuer of the asset to change the max supply of the asset afterwards.

Motivation

For crowd-sales, we would like to add measures that allow an issuer to guarantee to investors that the max supply of an asset cannot be changed in the future. With the importance that the 21Mio limit on Bitcoin has, we feel that this feature is important for BitShares as well.

Rational

After a crowd-sale or investment round, we want investors to feel safe that their token cannot be further diluted and that the blockchain ultimately supports that claim by preventing the issuer from changing the max supply once the proposed permission is toggled.

Specifications

We introduce a new flag for asset_issuer_permission_flags with the name disable_modify_max_supply. This flag will be tested in the evaluator of asset_update_operation which is the only operation that can change the max_supply value of an asset.

Obviously, even if this permissions and flags are toggled and the max_supply cannot be changed, the operation asset_issue will still work up to the max supply allowed.

Discussion

It remains to be discussed how to initialize the newly introduced value for existing assets.
A first pull request against bitshares-core is available here.

Summary for Shareholders

This proposal is particular useful as it allows to set limits to dilution of a token. Not even the issuer will be able to change max supply when the newly introduced flag and permission are toggled.

Copyright

Public Domain

[xeroc]

closing .. duplicate of #115