diff --git a/dapps/src/api/types.rs.in b/dapps/src/api/types.rs.in
index 8bbefaa83..a95a0d446 100644
--- a/dapps/src/api/types.rs.in
+++ b/dapps/src/api/types.rs.in
@@ -17,6 +17,7 @@
 use endpoint::EndpointInfo;
 
 #[derive(Debug, PartialEq, Clone, Serialize, Deserialize)]
+#[serde(deny_unknown_fields)]
 pub struct App {
 	pub id: String,
 	pub name: String,
@@ -54,6 +55,7 @@ impl Into<EndpointInfo> for App {
 }
 
 #[derive(Debug, PartialEq, Serialize, Deserialize)]
+#[serde(deny_unknown_fields)]
 pub struct ApiError {
 	pub code: String,
 	pub title: String,
diff --git a/rpc/src/v1/types/call_request.rs b/rpc/src/v1/types/call_request.rs
index 38721e2f8..015811273 100644
--- a/rpc/src/v1/types/call_request.rs
+++ b/rpc/src/v1/types/call_request.rs
@@ -19,6 +19,7 @@ use v1::types::{Bytes, H160, U256};
 
 /// Call request
 #[derive(Debug, Default, PartialEq, Deserialize)]
+#[serde(deny_unknown_fields)]
 pub struct CallRequest {
 	/// From
 	pub from: Option<H160>,
diff --git a/rpc/src/v1/types/confirmations.rs b/rpc/src/v1/types/confirmations.rs
index 2b7813df9..bbbad83f3 100644
--- a/rpc/src/v1/types/confirmations.rs
+++ b/rpc/src/v1/types/confirmations.rs
@@ -137,6 +137,7 @@ impl From<helpers::ConfirmationPayload> for ConfirmationPayload {
 
 /// Possible modifications to the confirmed transaction sent by `Trusted Signer`
 #[derive(Debug, PartialEq, Deserialize)]
+#[serde(deny_unknown_fields)]
 pub struct TransactionModification {
 	/// Modified gas price
 	#[serde(rename="gasPrice")]
diff --git a/rpc/src/v1/types/histogram.rs b/rpc/src/v1/types/histogram.rs
index 385038b56..f7bb5525a 100644
--- a/rpc/src/v1/types/histogram.rs
+++ b/rpc/src/v1/types/histogram.rs
@@ -21,6 +21,7 @@ use util::stats;
 
 /// Values of RPC settings.
 #[derive(Serialize, Deserialize)]
+#[serde(deny_unknown_fields)]
 pub struct Histogram {
 	/// Gas prices for bucket edges.
 	#[serde(rename="bucketBounds")]
diff --git a/rpc/src/v1/types/rpc_settings.rs b/rpc/src/v1/types/rpc_settings.rs
index 9a20afa7a..de8f90410 100644
--- a/rpc/src/v1/types/rpc_settings.rs
+++ b/rpc/src/v1/types/rpc_settings.rs
@@ -18,6 +18,7 @@
 
 /// Values of RPC settings.
 #[derive(Serialize, Deserialize)]
+#[serde(deny_unknown_fields)]
 pub struct RpcSettings {
 	/// Whether RPC is enabled.
 	pub enabled: bool,
@@ -25,4 +26,4 @@ pub struct RpcSettings {
 	pub interface: String,
 	/// The port being listened on.
 	pub port: u64,
-}
\ No newline at end of file
+}
diff --git a/rpc/src/v1/types/trace_filter.rs b/rpc/src/v1/types/trace_filter.rs
index 21e50e175..6c7460f9b 100644
--- a/rpc/src/v1/types/trace_filter.rs
+++ b/rpc/src/v1/types/trace_filter.rs
@@ -22,6 +22,7 @@ use v1::types::{BlockNumber, H160};
 
 /// Trace filter
 #[derive(Debug, PartialEq, Deserialize)]
+#[serde(deny_unknown_fields)]
 pub struct TraceFilter {
 	/// From block
 	#[serde(rename="fromBlock")]
diff --git a/rpc/src/v1/types/transaction_request.rs b/rpc/src/v1/types/transaction_request.rs
index b7ee1f47d..a4f8e6387 100644
--- a/rpc/src/v1/types/transaction_request.rs
+++ b/rpc/src/v1/types/transaction_request.rs
@@ -21,6 +21,7 @@ use v1::helpers;
 
 /// Transaction request coming from RPC
 #[derive(Debug, Clone, Default, Eq, PartialEq, Hash, Serialize, Deserialize)]
+#[serde(deny_unknown_fields)]
 pub struct TransactionRequest {
 	/// Sender
 	pub from: H160,