diff --git a/libsolidity/AST.h b/libsolidity/AST.h
index f5f6a3f38..335b9a880 100644
--- a/libsolidity/AST.h
+++ b/libsolidity/AST.h
@@ -553,17 +553,24 @@ private:
 class EventDefinition: public Declaration, public VariableScope, public Documented
 {
 public:
-	EventDefinition(SourceLocation const& _location,
-					ASTPointer<ASTString> const& _name,
-					ASTPointer<ASTString> const& _documentation,
-					ASTPointer<ParameterList> const& _parameters):
-		Declaration(_location, _name), Documented(_documentation), m_parameters(_parameters) {}
+	EventDefinition(
+		SourceLocation const& _location,
+		ASTPointer<ASTString> const& _name,
+		ASTPointer<ASTString> const& _documentation,
+		ASTPointer<ParameterList> const& _parameters,
+		bool _anonymous = false
+	):
+		Declaration(_location, _name),
+		Documented(_documentation),
+		m_parameters(_parameters),
+		m_anonymous(_anonymous){}
 
 	virtual void accept(ASTVisitor& _visitor) override;
 	virtual void accept(ASTConstVisitor& _visitor) const override;
 
 	std::vector<ASTPointer<VariableDeclaration>> const& getParameters() const { return m_parameters->getParameters(); }
 	ParameterList const& getParameterList() const { return *m_parameters; }
+	bool isAnonymous() const { return m_anonymous; }
 
 	virtual TypePointer getType(ContractDefinition const* = nullptr) const override
 	{
@@ -574,6 +581,7 @@ public:
 
 private:
 	ASTPointer<ParameterList> m_parameters;
+	bool m_anonymous = false;
 };
 
 /**
diff --git a/libsolidity/ExpressionCompiler.cpp b/libsolidity/ExpressionCompiler.cpp
index a0a688bbd..61b17f663 100644
--- a/libsolidity/ExpressionCompiler.cpp
+++ b/libsolidity/ExpressionCompiler.cpp
@@ -542,8 +542,11 @@ bool ExpressionCompiler::visit(FunctionCall const& _functionCall)
 					appendTypeConversion(*arguments[arg - 1]->getType(),
 										 *function.getParameterTypes()[arg - 1], true);
 				}
-			m_context << u256(h256::Arith(dev::sha3(function.getCanonicalSignature(event.getName()))));
-			++numIndexed;
+			if (!event.isAnonymous())
+			{
+				m_context << u256(h256::Arith(dev::sha3(function.getCanonicalSignature(event.getName()))));
+				++numIndexed;
+			}
 			solAssert(numIndexed <= 4, "Too many indexed arguments.");
 			// Copy all non-indexed arguments to memory (data)
 			m_context << u256(0);
diff --git a/libsolidity/InterfaceHandler.cpp b/libsolidity/InterfaceHandler.cpp
index 99a7db96e..406d1e24a 100644
--- a/libsolidity/InterfaceHandler.cpp
+++ b/libsolidity/InterfaceHandler.cpp
@@ -70,6 +70,7 @@ std::unique_ptr<std::string> InterfaceHandler::getABIInterface(ContractDefinitio
 		Json::Value event;
 		event["type"] = "event";
 		event["name"] = it->getName();
+		event["anonymous"] = it->isAnonymous();
 		Json::Value params(Json::arrayValue);
 		for (auto const& p: it->getParameters())
 		{
diff --git a/libsolidity/Parser.cpp b/libsolidity/Parser.cpp
index 459a34bd0..393d2734e 100644
--- a/libsolidity/Parser.cpp
+++ b/libsolidity/Parser.cpp
@@ -394,9 +394,15 @@ ASTPointer<EventDefinition> Parser::parseEventDefinition()
 		parameters = parseParameterList(true, true);
 	else
 		parameters = createEmptyParameterList();
+	bool anonymous = false;
+	if (m_scanner->getCurrentToken() == Token::Anonymous)
+	{
+		anonymous = true;
+		m_scanner->next();
+	}
 	nodeFactory.markEndPosition();
 	expectToken(Token::Semicolon);
-	return nodeFactory.createNode<EventDefinition>(name, docstring, parameters);
+	return nodeFactory.createNode<EventDefinition>(name, docstring, parameters, anonymous);
 }
 
 ASTPointer<ModifierInvocation> Parser::parseModifierInvocation()
diff --git a/libsolidity/Token.h b/libsolidity/Token.h
index 2d8a49fcd..b2951e939 100644
--- a/libsolidity/Token.h
+++ b/libsolidity/Token.h
@@ -145,6 +145,7 @@ namespace solidity
 	K(Break, "break", 0)                                               \
 	K(Case, "case", 0)                                                 \
 	K(Const, "constant", 0)                                            \
+	K(Anonymous, "anonymous", 0)                                       \
 	K(Continue, "continue", 0)                                         \
 	K(Contract, "contract", 0)                                         \
 	K(Default, "default", 0)                                           \
diff --git a/test/SolidityABIJSON.cpp b/test/SolidityABIJSON.cpp
index 195270138..f7f968ea8 100644
--- a/test/SolidityABIJSON.cpp
+++ b/test/SolidityABIJSON.cpp
@@ -309,6 +309,7 @@ BOOST_AUTO_TEST_CASE(events)
 	{
 		"name": "e1",
 		"type": "event",
+		"anonymous": false,
 		"inputs": [
 		{
 			"indexed": false,
@@ -325,6 +326,7 @@ BOOST_AUTO_TEST_CASE(events)
 	{
 		"name": "e2",
 		"type": "event",
+		"anonymous": false,
 		"inputs": []
 	}
 
@@ -333,6 +335,23 @@ BOOST_AUTO_TEST_CASE(events)
 	checkInterface(sourceCode, interface);
 }
 
+BOOST_AUTO_TEST_CASE(events_anonymous)
+{
+	char const* sourceCode = "contract test {\n"
+	"  event e() anonymous; \n"
+	"}\n";
+	char const* interface = R"([
+	{
+		"name": "e",
+		"type": "event",
+		"anonymous": true,
+		"inputs": []
+	}
+
+	])";
+
+	checkInterface(sourceCode, interface);
+}
 
 BOOST_AUTO_TEST_CASE(inherited)
 {
@@ -380,6 +399,7 @@ BOOST_AUTO_TEST_CASE(inherited)
 	{
 		"name": "derivedEvent",
 		"type": "event",
+		"anonymous": false,
 		"inputs":
 		[{
 			"indexed": true,
@@ -390,6 +410,7 @@ BOOST_AUTO_TEST_CASE(inherited)
 	{
 		"name": "baseEvent",
 		"type": "event",
+		"anonymous": false,
 		"inputs":
 		[{
 			"indexed": true,
diff --git a/test/SolidityEndToEndTest.cpp b/test/SolidityEndToEndTest.cpp
index e4b55514d..ce7a472bc 100644
--- a/test/SolidityEndToEndTest.cpp
+++ b/test/SolidityEndToEndTest.cpp
@@ -2202,6 +2202,43 @@ BOOST_AUTO_TEST_CASE(event_no_arguments)
 	BOOST_CHECK_EQUAL(m_logs[0].topics[0], dev::sha3(string("Deposit()")));
 }
 
+BOOST_AUTO_TEST_CASE(event_anonymous)
+{
+	char const* sourceCode = R"(
+		contract ClientReceipt {
+			event Deposit() anonymous;
+			function deposit() {
+				Deposit();
+			}
+		}
+	)";
+	compileAndRun(sourceCode);
+	callContractFunction("deposit()");
+	BOOST_REQUIRE_EQUAL(m_logs[0].topics.size(), 0);
+}
+
+BOOST_AUTO_TEST_CASE(event_anonymous_with_topics)
+{
+	char const* sourceCode = R"(
+		contract ClientReceipt {
+			event Deposit(address indexed _from, bytes32 indexed _id, uint _value) anonymous;
+			function deposit(bytes32 _id, bool _manually) {
+				Deposit(msg.sender, _id, msg.value);
+			}
+		}
+	)";
+	compileAndRun(sourceCode);
+	u256 value(18);
+	u256 id(0x1234);
+	callContractFunctionWithValue("deposit(bytes32,bool)", value, id);
+	BOOST_REQUIRE_EQUAL(m_logs.size(), 1);
+	BOOST_CHECK_EQUAL(m_logs[0].address, m_contractAddress);
+	BOOST_CHECK_EQUAL(h256(m_logs[0].data), h256(u256(value)));
+	BOOST_REQUIRE_EQUAL(m_logs[0].topics.size(), 2);
+	BOOST_CHECK_EQUAL(m_logs[0].topics[0], h256(m_sender));
+	BOOST_CHECK_EQUAL(m_logs[0].topics[1], h256(id));
+}
+
 BOOST_AUTO_TEST_CASE(event_lots_of_data)
 {
 	char const* sourceCode = R"(