diff --git a/ethcore/src/chainfilter/chainfilter.rs b/ethcore/src/chainfilter/chainfilter.rs
index e0a281f12..fb6df877a 100644
--- a/ethcore/src/chainfilter/chainfilter.rs
+++ b/ethcore/src/chainfilter/chainfilter.rs
@@ -110,9 +110,8 @@ impl<'a, D> ChainFilter<'a, D> where D: FilterDataSource
 			// map them to offsets
 			.map(|li| li.index * level_size)
 			// get all blocks that may contain our bloom
-			.map(|off| self.blocks(bloom, from_block, to_block, level - 1, off))
 			// filter existing ones
-			.filter_map(|x| x)
+			.filter_map(|off| self.blocks(bloom, from_block, to_block, level - 1, off))
 			// flatten nested structures
 			.flat_map(|v| v)
 			.collect();
@@ -161,9 +160,8 @@ impl<'a, D> ChainFilter<'a, D> where D: FilterDataSource
 					self.indexer.lower_level_bloom_indexes(&index)
 						.into_iter()
 						// get blooms
-						.map(bloom_at)
 						// filter existing ones
-						.filter_map(|b| b)
+						.filter_map(bloom_at)
 						// BitOr all of them
 						.fold(H2048::new(), |acc, bloom| acc | bloom)
 				};
diff --git a/ethcore/src/client.rs b/ethcore/src/client.rs
index 18ce28c6b..9244c26fc 100644
--- a/ethcore/src/client.rs
+++ b/ethcore/src/client.rs
@@ -482,8 +482,7 @@ impl BlockChainClient for Client {
 
 	fn logs(&self, filter: Filter) -> Vec<LocalizedLogEntry> {
 		let mut blocks = filter.bloom_possibilities().iter()
-			.map(|bloom| self.blocks_with_bloom(bloom, filter.from_block.clone(), filter.to_block.clone()))
-			.filter_map(|m| m)
+			.filter_map(|bloom| self.blocks_with_bloom(bloom, filter.from_block.clone(), filter.to_block.clone()))
 			.flat_map(|m| m)
 			// remove duplicate elements
 			.collect::<HashSet<u64>>()
@@ -493,17 +492,14 @@ impl BlockChainClient for Client {
 		blocks.sort();
 
 		blocks.into_iter()
-			.map(|number| self.chain.read().unwrap().block_hash(number).map(|hash| (number, hash)))
-			.filter_map(|m| m)
-			.map(|(number, hash)| self.chain.read().unwrap().block_receipts(&hash).map(|r| (number, hash, r.receipts)))
-			.filter_map(|m| m)
-			.map(|(number, hash, receipts)| self.chain.read().unwrap().block(&hash).map(|ref b| (number, hash, receipts, BlockView::new(b).transaction_hashes())))
-			.filter_map(|m| m)
-			.map(|(number, hash, receipts, hashes)| {
+			.filter_map(|number| self.chain.read().unwrap().block_hash(number).map(|hash| (number, hash)))
+			.filter_map(|(number, hash)| self.chain.read().unwrap().block_receipts(&hash).map(|r| (number, hash, r.receipts)))
+			.filter_map(|(number, hash, receipts)| self.chain.read().unwrap().block(&hash).map(|ref b| (number, hash, receipts, BlockView::new(b).transaction_hashes())))
+			.flat_map(|(number, hash, receipts, hashes)| {
 				let mut log_index = 0;
 				receipts.into_iter()
 					.enumerate()
-					.map(|(index, receipt)| {
+					.flat_map(|(index, receipt)| {
 						log_index += receipt.logs.len();
 						receipt.logs.into_iter()
 							.enumerate()
@@ -518,11 +514,9 @@ impl BlockChainClient for Client {
 							})
 							.collect::<Vec<LocalizedLogEntry>>()
 					})
-					.flat_map(|m| m)
 					.collect::<Vec<LocalizedLogEntry>>()
 					
 			})
-			.flat_map(|m| m)
 			.collect()
 	}
 }