diff --git a/src/main.cpp b/src/main.cpp
index 93079693c31..bd5b2408a0e 100644
--- a/src/main.cpp
+++ b/src/main.cpp
@@ -2239,6 +2239,29 @@ bool ProcessBlock(CNode* pfrom, CBlock* pblock, CDiskBlockPos *dbp)
 
 
 
+CMerkleBlock::CMerkleBlock(const CBlock& block, CBloomFilter& filter)
+{
+    header = block.GetBlockHeader();
+    vtx.reserve(block.vtx.size());
+
+    for(unsigned int i = 0; i < block.vtx.size(); i++)
+    {
+        vector<uint256> branch = block.GetMerkleBranch(i);
+        uint256 hash = block.vtx[i].GetHash();
+        if (filter.IsRelevantAndUpdate(block.vtx[i], hash))
+        {
+            vtx.push_back(make_tuple(i, hash, branch));
+        }
+    }
+}
+
+
+
+
+
+
+
+
 bool CheckDiskSpace(uint64 nAdditionalBytes)
 {
     uint64 nFreeBytesAvailable = filesystem::space(GetDataDir()).available;
diff --git a/src/main.h b/src/main.h
index d2329af09ae..77aac71d225 100644
--- a/src/main.h
+++ b/src/main.h
@@ -2039,4 +2039,34 @@ struct CBlockTemplate
     std::vector<int64_t> vTxSigOps;
 };
 
+
+
+
+
+
+/** Used to relay blocks as header + vector<merkle branch>
+ * to filtered nodes.
+ */
+class CMerkleBlock
+{
+public:
+    CBlockHeader header;
+
+    // We could optimize this a bit to deduplicate partial branches,
+    // but it's not worth much unless a node has a ton of txes in a single block
+    //                       tx index    , tx hash, merkle branch
+    std::vector<boost::tuple<unsigned int, uint256, std::vector<uint256> > > vtx;
+
+    // Create from a CBlock, filtering transactions according to filter
+    // Note that this will call IsRelevantAndUpdate on the filter for each transaction,
+    // thus the filter will likely be modified.
+    CMerkleBlock(const CBlock& block, CBloomFilter& filter);
+
+    IMPLEMENT_SERIALIZE
+    (
+        READWRITE(header);
+        READWRITE(vtx);
+    )
+};
+
 #endif