TIP-4.8 (ITransferableNft) standard description

src/standard/TIP-4/8.md

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+---
+title: 4.8. Transferable NFT
+sidebar_position: 8
+slug: /standard/TIP-4.8
+---
+
+# Transferable NFT (TIP-4.7)
+Requires: [TIP-4.1](1.md)
+Requires: [TIP-6.1](./../TIP-6/1.md)
+
+## Abstract
+
+This standard provides information on the availability of NFT change of ownership
+
+## Motivation
+
+The [TIP-4.1](1.md) standard includes only the event to be triggered by an NFT transfer and does not provide any additional information. 
+At the same time, some contracts should not be able to be transferred to another owner. 
+In such a case, the transfer will not work and the dapp must know this in order to provide information about it to the user and not to call inactive functions
+
+```solidity
+interface ITIP4_8 {
+		event TransferLocked();
+    event TransferUnlocked();
+
+    function isTransferable() external responsible view returns(bool);
+}
+```
+
+**TIP4_8.transferable()**
+
+```solidity
+function isTransferable() external responsible view returns(bool);
+```
+
+Returns information about whether the transfer is available. This value may change if lock/unlock is provided by the implementation
+
+### Events
+
+```solidity
+event TransferLocked();
+event TransferUnlocked();
+```
+
+**TransferLocked**
+
+You MUST emit it when the transfer is locked
+
+**TransferUnlocked**
+
+You MUST emit it when the transfer is unlocked. If unlocking occurs just before the transfer itself (e.g. there was a timed lock), the event MUST also be emited together with the unlocking