diff --git a/lib/blocks.js b/lib/blocks.js
index a534c51..89d6113 100644
--- a/lib/blocks.js
+++ b/lib/blocks.js
@@ -151,7 +151,7 @@ BlockController.prototype.transformBlock = function(block, info) {
     previousblockhash: info.prevHash,
     nextblockhash: info.nextHash,
     reward: this.getBlockReward(block.txs[0]),
-    isMainChain: block.isMainChain,
+    isMainChain: true,
     poolInfo: this.getPoolInfo(block.txs[0])
   };
 };