Upgradeable security token

A computerized method for upgrading a parent smart contract, wherein the computerized method is performed by a network node configured to be included within a plurality of network nodes in a peer-to-peer network of network nodes implementing a distributed ledger, wherein the network node is configured to be communicatively coupled to other network nodes in the peer-to-peer network, the computerized method comprising:

• deploying a child smart contract, which is a subsequent version of the parent smart contract, on the distributed ledger;
• and
• setting an upgraded address field in the parent smart contract to point to an address of the child smart contract;
• wherein the parent smart contract remains deployed after the child smart contract is deployed.

A network node comprising:

• at least one processor;
• at least one memory communicatively coupled to the at least one processor;
• at least one network interface communicatively couple to the at least one processor;
• wherein the network node is configured to be within a plurality of network nodes communicatively coupled in a peer-to-peer network of network nodes implementing a distributed ledger;
• wherein the network node is configured to be communicatively coupled to at least one remotely located computing device through the at least one network interface;
• wherein the at least one processor is configured to:
• deploy a child smart contract, which is a subsequent version of a parent smart contract, on the distributed ledger;
• set an upgraded address field in the parent smart contract to point to an address of the child smart contract;
• issue new tokens in the child smart contract to an intermediate address;
• migrate all old tokens in the parent smart contract from a token holder address to an address of the child smart contract;
• and
• transfer at least one new token in the child smart contract from the intermediate address to the token holder address;
• wherein the parent smart contract remains deployed after the child smart contract is deployed;
• and
• wherein the old tokens and new tokens are cryptographic tokens that each represents an external, tradable asset.