diff --git a/packages/protocol/contracts/L1/TaikoData.sol b/packages/protocol/contracts/L1/TaikoData.sol
index 8b08b699a1..d2729e062d 100644
--- a/packages/protocol/contracts/L1/TaikoData.sol
+++ b/packages/protocol/contracts/L1/TaikoData.sol
@@ -72,7 +72,6 @@ library TaikoData {
 
     struct BlockParamsV2 {
         address coinbase;
-        bytes32 extraData;
         bytes32 parentMetaHash;
         uint64 anchorBlockId; // NEW
         uint64 timestamp; // NEW
@@ -125,7 +124,6 @@ library TaikoData {
         uint32 blobTxListLength;
         uint8 blobIndex;
         uint8 basefeeAdjustmentQuotient;
-        uint8 basefeeSharingPctg;
         uint32 gasIssuancePerSecond;
     }
 
diff --git a/packages/protocol/contracts/L1/libs/LibData.sol b/packages/protocol/contracts/L1/libs/LibData.sol
index f497b7fa0a..f25a26a8fc 100644
--- a/packages/protocol/contracts/L1/libs/LibData.sol
+++ b/packages/protocol/contracts/L1/libs/LibData.sol
@@ -18,7 +18,6 @@ library LibData {
     {
         return TaikoData.BlockParamsV2({
             coinbase: _v1.coinbase,
-            extraData: _v1.extraData,
             parentMetaHash: _v1.parentMetaHash,
             anchorBlockId: 0,
             timestamp: 0,
@@ -77,7 +76,6 @@ library LibData {
             blobTxListLength: 0,
             blobIndex: 0,
             basefeeAdjustmentQuotient: 0,
-            basefeeSharingPctg: 0,
             gasIssuancePerSecond: 0
         });
     }
diff --git a/packages/protocol/contracts/L1/libs/LibProposing.sol b/packages/protocol/contracts/L1/libs/LibProposing.sol
index 14afcf4f5c..7dda7cdf3f 100644
--- a/packages/protocol/contracts/L1/libs/LibProposing.sol
+++ b/packages/protocol/contracts/L1/libs/LibProposing.sol
@@ -20,6 +20,7 @@ library LibProposing {
         ITierProvider tierProvider;
         bytes32 parentMetaHash;
         bool postFork;
+        bytes32 extraData;
     }
 
     /// @notice Emitted when a block is proposed.
@@ -96,7 +97,9 @@ library LibProposing {
                 // otherwise use a default BlockParamsV2 with 0 values
             }
         } else {
-            local.params = LibData.blockParamsV1ToV2(abi.decode(_data, (TaikoData.BlockParams)));
+            TaikoData.BlockParams memory paramsV1 = abi.decode(_data, (TaikoData.BlockParams));
+            local.params = LibData.blockParamsV1ToV2(paramsV1);
+            local.extraData = paramsV1.extraData;
         }
 
         if (local.params.coinbase == address(0)) {
@@ -158,7 +161,12 @@ library LibProposing {
                 anchorBlockHash: blockhash(local.params.anchorBlockId),
                 difficulty: keccak256(abi.encode("TAIKO_DIFFICULTY", local.b.numBlocks)),
                 blobHash: 0, // to be initialized below
-                extraData: local.params.extraData,
+                // To make sure each L2 block can be exexucated deterministiclly by the client
+                // without referering to its metadata on Ethereum, we need to encode
+                // config.basefeeSharingPctg into the extraData.
+                extraData: local.postFork
+                    ? _encodeGasConfigs(_config.basefeeSharingPctg)
+                    : local.extraData,
                 coinbase: local.params.coinbase,
                 id: local.b.numBlocks,
                 gasLimit: _config.blockMaxGasLimit,
@@ -175,7 +183,6 @@ library LibProposing {
                 blobTxListLength: local.params.blobTxListLength,
                 blobIndex: local.params.blobIndex,
                 basefeeAdjustmentQuotient: _config.basefeeAdjustmentQuotient,
-                basefeeSharingPctg: _config.basefeeSharingPctg,
                 gasIssuancePerSecond: _config.gasIssuancePerSecond
             });
         }
@@ -262,4 +269,8 @@ library LibProposing {
             revert L1_INVALID_PROPOSER();
         }
     }
+
+    function _encodeGasConfigs(uint8 _basefeeSharingPctg) private pure returns (bytes32) {
+        return bytes32(uint256(_basefeeSharingPctg));
+    }
 }
diff --git a/packages/protocol/test/L1/TaikoL1testGroupA2.t.sol b/packages/protocol/test/L1/TaikoL1testGroupA2.t.sol
index a872e25185..49c9a78a27 100644
--- a/packages/protocol/test/L1/TaikoL1testGroupA2.t.sol
+++ b/packages/protocol/test/L1/TaikoL1testGroupA2.t.sol
@@ -50,7 +50,6 @@ contract TaikoL1TestGroupA2 is TaikoL1TestGroupBase {
             assertEq(meta.anchorBlockHash, blockhash(block.number - 1));
             assertEq(meta.livenessBond, config.livenessBond);
             assertEq(meta.coinbase, Alice);
-            assertEq(meta.extraData, params.extraData);
 
             TaikoData.Block memory blk = L1.getBlock(i);
             assertEq(blk.blockId, i);
@@ -104,7 +103,6 @@ contract TaikoL1TestGroupA2 is TaikoL1TestGroupBase {
         // Propose the first block with default parameters
         TaikoData.BlockParamsV2 memory params = TaikoData.BlockParamsV2({
             coinbase: address(0),
-            extraData: 0,
             parentMetaHash: 0,
             anchorBlockId: 0,
             timestamp: 0,
@@ -125,7 +123,6 @@ contract TaikoL1TestGroupA2 is TaikoL1TestGroupBase {
         assertEq(meta.livenessBond, config.livenessBond);
         assertEq(meta.coinbase, Alice);
         assertEq(meta.parentMetaHash, bytes32(uint256(1)));
-        assertEq(meta.extraData, params.extraData);
 
         TaikoData.Block memory blk = L1.getBlock(1);
         assertEq(blk.blockId, 1);
@@ -145,7 +142,6 @@ contract TaikoL1TestGroupA2 is TaikoL1TestGroupBase {
 
         params = TaikoData.BlockParamsV2({
             coinbase: Bob,
-            extraData: bytes32(uint256(123)),
             parentMetaHash: 0,
             anchorBlockId: 90,
             timestamp: uint64(block.timestamp - 100),
@@ -165,7 +161,6 @@ contract TaikoL1TestGroupA2 is TaikoL1TestGroupBase {
         assertEq(meta.livenessBond, config.livenessBond);
         assertEq(meta.coinbase, Bob);
         assertEq(meta.parentMetaHash, blk.metaHash);
-        assertEq(meta.extraData, params.extraData);
 
         blk = L1.getBlock(2);
         assertEq(blk.blockId, 2);