diff --git a/CHANGELOG.md b/CHANGELOG.md
index 809742722..061f25db6 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -1,3 +1,20 @@
+## Parity-Ethereum [v2.5.12](https://github.com/paritytech/parity-ethereum/releases/tag/v2.5.12)
+
+Parity Ethereum v2.5.12-stable is a patch release that adds Istanbul hardfork
+block numbers for POA and xDai networks, implements ECIP-1056 and implements
+EIP-2384/2387 - Muir Glacier.
+
+The full list of included changes:
+* Enable EIP-2384 for ice age hard fork (#11281)
+* ethcore/res: activate agharta on classic 9573000 (#11331)
+* Istanbul HF in xDai (2019-12-12) (#11299)
+* Istanbul HF in POA Core (2019-12-19) (#11298)
+* Istanbul HF in POA Sokol (2019-12-05) (#11282)
+* Activate ecip-1061 on kotti and mordor (#11338)
+* Enable basic verification of local transactions (#11332)
+* Disallow EIP-86 style null signatures for transactions outside tests (#11335)
+
+
 ## Parity-Ethereum [v2.5.11](https://github.com/paritytech/parity-ethereum/releases/tag/v2.5.11)
 
 Parity Ethereum v2.5.11-stable is an emergency patch release that adds the missing
diff --git a/Cargo.lock b/Cargo.lock
index f0588ce22..0be3e4cf9 100644
--- a/Cargo.lock
+++ b/Cargo.lock
@@ -2726,7 +2726,7 @@ dependencies = [
  "futures 0.1.29 (registry+https://github.com/rust-lang/crates.io-index)",
  "jni 0.11.0 (registry+https://github.com/rust-lang/crates.io-index)",
  "panic_hook 0.1.0",
- "parity-ethereum 2.5.11",
+ "parity-ethereum 2.5.12",
  "tokio 0.1.22 (registry+https://github.com/rust-lang/crates.io-index)",
  "tokio-current-thread 0.1.6 (registry+https://github.com/rust-lang/crates.io-index)",
 ]
@@ -2783,7 +2783,7 @@ dependencies = [
 
 [[package]]
 name = "parity-ethereum"
-version = "2.5.11"
+version = "2.5.12"
 dependencies = [
  "ansi_term 0.10.2 (registry+https://github.com/rust-lang/crates.io-index)",
  "atty 0.2.13 (registry+https://github.com/rust-lang/crates.io-index)",
@@ -2836,7 +2836,7 @@ dependencies = [
  "parity-rpc 1.12.0",
  "parity-runtime 0.1.0",
  "parity-updater 1.12.0",
- "parity-version 2.5.11",
+ "parity-version 2.5.12",
  "parity-whisper 0.1.0",
  "parking_lot 0.7.1 (registry+https://github.com/rust-lang/crates.io-index)",
  "pretty_assertions 0.1.2 (registry+https://github.com/rust-lang/crates.io-index)",
@@ -2982,7 +2982,7 @@ dependencies = [
  "parity-crypto 0.3.1 (registry+https://github.com/rust-lang/crates.io-index)",
  "parity-runtime 0.1.0",
  "parity-updater 1.12.0",
- "parity-version 2.5.11",
+ "parity-version 2.5.12",
  "parking_lot 0.7.1 (registry+https://github.com/rust-lang/crates.io-index)",
  "pretty_assertions 0.1.2 (registry+https://github.com/rust-lang/crates.io-index)",
  "rand 0.4.6 (registry+https://github.com/rust-lang/crates.io-index)",
@@ -3080,7 +3080,7 @@ dependencies = [
  "parity-bytes 0.1.1 (registry+https://github.com/rust-lang/crates.io-index)",
  "parity-hash-fetch 1.12.0",
  "parity-path 0.1.2 (registry+https://github.com/rust-lang/crates.io-index)",
- "parity-version 2.5.11",
+ "parity-version 2.5.12",
  "parking_lot 0.7.1 (registry+https://github.com/rust-lang/crates.io-index)",
  "rand 0.4.6 (registry+https://github.com/rust-lang/crates.io-index)",
  "semver 0.9.0 (registry+https://github.com/rust-lang/crates.io-index)",
@@ -3090,7 +3090,7 @@ dependencies = [
 
 [[package]]
 name = "parity-version"
-version = "2.5.11"
+version = "2.5.12"
 dependencies = [
  "parity-bytes 0.1.1 (registry+https://github.com/rust-lang/crates.io-index)",
  "rlp 0.3.0 (registry+https://github.com/rust-lang/crates.io-index)",
diff --git a/Cargo.toml b/Cargo.toml
index 56b1cb000..9ce76e032 100644
--- a/Cargo.toml
+++ b/Cargo.toml
@@ -2,7 +2,7 @@
 description = "Parity Ethereum client"
 name = "parity-ethereum"
 # NOTE Make sure to update util/version/Cargo.toml as well
-version = "2.5.11"
+version = "2.5.12"
 license = "GPL-3.0"
 authors = ["Parity Technologies <admin@parity.io>"]
 
diff --git a/ethcore/res/ethereum/classic.json b/ethcore/res/ethereum/classic.json
index 200fa823c..d598a4ec9 100644
--- a/ethcore/res/ethereum/classic.json
+++ b/ethcore/res/ethereum/classic.json
@@ -37,7 +37,10 @@
 		"eip140Transition": "0x85d9a0",
 		"eip211Transition": "0x85d9a0",
 		"eip214Transition": "0x85d9a0",
-		"eip658Transition": "0x85d9a0"
+		"eip658Transition": "0x85d9a0",
+		"eip145Transition": "0x921288",
+		"eip1014Transition": "0x921288",
+		"eip1052Transition": "0x921288"
 	},
 	"genesis": {
 		"seal": {
diff --git a/ethcore/res/ethereum/foundation.json b/ethcore/res/ethereum/foundation.json
index 417b6fbe0..48550d7df 100644
--- a/ethcore/res/ethereum/foundation.json
+++ b/ethcore/res/ethereum/foundation.json
@@ -136,7 +136,8 @@
 				"eip100bTransition": "0x42ae50",
 				"difficultyBombDelays": {
 					"0x42ae50": "0x2dc6c0",
-					"0x6f1580": "0x1e8480"
+					"0x6f1580": "0x1e8480",
+					"0x8c6180": "0x3d0900"
 				}
 			}
 		}
diff --git a/ethcore/res/ethereum/kotti.json b/ethcore/res/ethereum/kotti.json
index 7876fe8cd..25ba61961 100644
--- a/ethcore/res/ethereum/kotti.json
+++ b/ethcore/res/ethereum/kotti.json
@@ -24,6 +24,10 @@
 		"eip658Transition": "0xaef49",
 		"eip1014Transition": "0x1a064d",
 		"eip1052Transition": "0x1a064d",
+		"eip1283Transition": "0x1f67cf",
+		"eip1344Transition": "0x1f67cf",
+		"eip1706Transition": "0x1f67cf",
+		"eip2028Transition": "0x1f67cf",
 		"gasLimitBoundDivisor": "0x400",
 		"maxCodeSize": "0x6000",
 		"maxCodeSizeTransition": "0xaef49",
@@ -123,7 +127,7 @@
 					"0xaef49": {
 						"price": { "alt_bn128_const_operations": { "price": 500 }}
 					},
-					"0x7fffffffffffff": {
+					"0x1f67cf": {
 						"info": "EIP 1108 transition",
 						"price": { "alt_bn128_const_operations": { "price": 150 }}
 					}
@@ -138,7 +142,7 @@
 					"0xaef49": {
 						"price": { "alt_bn128_const_operations": { "price": 40000 }}
 					},
-					"0x7fffffffffffff": {
+					"0x1f67cf": {
 						"info": "EIP 1108 transition",
 						"price": { "alt_bn128_const_operations": { "price": 6000 }}
 					}
@@ -153,7 +157,7 @@
 					"0xaef49": {
 						"price": { "alt_bn128_pairing": { "base": 100000, "pair": 80000 }}
 					},
-					"0x7fffffffffffff": {
+					"0x1f67cf": {
 						"info": "EIP 1108 transition",
 						"price": { "alt_bn128_pairing": { "base": 45000, "pair": 34000 }}
 					}
@@ -161,7 +165,16 @@
 			}
 		},
 		"0x0000000000000000000000000000000000000009": {
-			"balance": "0x1"
+			"balance": "0x1",
+			"builtin": {
+				"name": "blake2_f",
+				"activate_at": "0x1f67cf",
+				"pricing": {
+					"blake2_f": {
+						"gas_per_round": 1
+					}
+				}
+			}
 		},
 		"0x000000000000000000000000000000000000000a": {
 			"balance": "0x1"
diff --git a/ethcore/res/ethereum/mordor.json b/ethcore/res/ethereum/mordor.json
index ceaa9de6d..c5ae911f0 100644
--- a/ethcore/res/ethereum/mordor.json
+++ b/ethcore/res/ethereum/mordor.json
@@ -37,7 +37,11 @@
 		"eip658Transition":"0x0",
 		"eip145Transition":"0x498bb",
 		"eip1014Transition":"0x498bb",
-		"eip1052Transition":"0x498bb"
+		"eip1052Transition":"0x498bb",
+		"eip1283Transition":"0xbe10b",
+		"eip1344Transition":"0xbe10b",
+		"eip1706Transition":"0xbe10b",
+		"eip2028Transition":"0xbe10b"
 	},
 	"genesis":{
 		"seal":{
@@ -59,7 +63,9 @@
 		"enode://1813e90a0afdd7c1e4892c5376960e3577a9e6c5a4f86fa405a405c7421a4a1608248d77cc90333842f13d8954d82113dec480cfb76b4fef8cb475157cf4d5f2@10.28.224.3:30000",
 		"enode://2b69a3926f36a7748c9021c34050be5e0b64346225e477fe7377070f6289bd363b2be73a06010fd516e6ea3ee90778dd0399bc007bb1281923a79374f842675a@51.15.116.226:30303",
 		"enode://621e28e529146fd501709194885f50540c494f1a2985d1fb4ec8769226b5cb0b0d1a11545926077821474c2767cdd87888ead8a2509a2c9069dd5584e4b1c3b8@10.28.223.8:30000",
-		"enode://a59e33ccd2b3e52d578f1fbd70c6f9babda2650f0760d6ff3b37742fdcdfdb3defba5d56d315b40c46b70198c7621e63ffa3f987389c7118634b0fefbbdfa7fd@51.15.116.226:30303"
+		"enode://a59e33ccd2b3e52d578f1fbd70c6f9babda2650f0760d6ff3b37742fdcdfdb3defba5d56d315b40c46b70198c7621e63ffa3f987389c7118634b0fefbbdfa7fd@51.15.116.226:30303",
+		"enode://f840b007500f50c98ea6f9c9e56dabf4690bbbbb7036d43682c531204341aff8315013547e5bee54117eb22bd3603585ae6bf713d9fa710659533fcab65d5b84@35.238.101.58:30000",
+		"enode://19eda672030ad5debb98c9069b3e99d12438b96506325d9f3f82d76c5f8ce4942d345f41700a5223900e75ad48e76713b74c1b694d67a10c2112540035922256@35.238.101.58:30000"
 	],
 	"accounts":{
 		"0x0000000000000000000000000000000000000001":{
@@ -128,7 +134,7 @@
 							}
 						}
 					},
-					"0x7fffffffffffff":{
+					"0xbe10b":{
 						"info":"EIP 1108 transition",
 						"price":{
 							"alt_bn128_const_operations":{
@@ -150,7 +156,7 @@
 							}
 						}
 					},
-					"0x7fffffffffffff":{
+					"0xbe10b":{
 						"info":"EIP 1108 transition",
 						"price":{
 							"alt_bn128_const_operations":{
@@ -173,7 +179,7 @@
 							}
 						}
 					},
-					"0x7fffffffffffff":{
+					"0xbe10b":{
 						"info":"EIP 1108 transition",
 						"price":{
 							"alt_bn128_pairing":{
@@ -184,6 +190,17 @@
 					}
 				}
 			}
+		},
+		"0x0000000000000000000000000000000000000009": {
+			"builtin": {
+				"name": "blake2_f",
+				"activate_at": "0xbe10b",
+				"pricing": {
+					"blake2_f": {
+						"gas_per_round": 1
+					}
+				}
+			}
 		}
 	}
 }
diff --git a/ethcore/res/ethereum/poacore.json b/ethcore/res/ethereum/poacore.json
index 379dcd583..ecdd04c51 100644
--- a/ethcore/res/ethereum/poacore.json
+++ b/ethcore/res/ethereum/poacore.json
@@ -37,7 +37,12 @@
 		"eip658Transition": "0x0",
 		"eip145Transition": 8582254,
 		"eip1014Transition": 8582254,
-		"eip1052Transition": 8582254
+		"eip1052Transition": 8582254,
+		"eip1283Transition": 12598600,
+		"eip1344Transition": 12598600,
+		"eip1706Transition": 12598600,
+		"eip1884Transition": 12598600,
+		"eip2028Transition": 12598600
 	},
 	"genesis": {
 		"seal": {
@@ -58,57 +63,89 @@
 		"enode://96678da10ac83769ab3f63114a41b57b700476c5ac02719b878fa89909a936551bb7609aa09b068bf89903206fa03f23e1b5b9117ca278de304c2570b87dcb27@35.175.15.164:30303"
 	],
 	"accounts": {
-		"0000000000000000000000000000000000000005": { "builtin": { "name": "modexp", "activate_at": "0x0", "pricing": { "modexp": { "divisor": 20 } } } },
-		"0000000000000000000000000000000000000006": {
+		"0x0000000000000000000000000000000000000005": {
+			"builtin": {
+				"name": "modexp",
+				"pricing": {
+					"0": {
+						"price": {
+							"modexp": {
+								"divisor": 20
+							}
+						}
+					}
+				}
+			}
+		},
+		"0x0000000000000000000000000000000000000006": {
 			"builtin": {
 				"name": "alt_bn128_add",
 				"pricing": {
 					"0": {
 						"price": { "alt_bn128_const_operations": { "price": 500 }}
 					},
-					"0x7fffffffffffff": {
+					"12598600": {
 						"info": "EIP 1108 transition",
 						"price": { "alt_bn128_const_operations": { "price": 150 }}
 					}
 				}
 			}
 		},
-		"0000000000000000000000000000000000000007": {
+		"0x0000000000000000000000000000000000000007": {
 			"builtin": {
 				"name": "alt_bn128_mul",
 				"pricing": {
 					"0": {
 						"price": { "alt_bn128_const_operations": { "price": 40000 }}
 					},
-					"0x7fffffffffffff": {
+					"12598600": {
 						"info": "EIP 1108 transition",
 						"price": { "alt_bn128_const_operations": { "price": 6000 }}
 					}
 				}
 			}
 		},
-		"0000000000000000000000000000000000000008": {
+		"0x0000000000000000000000000000000000000008": {
 			"builtin": {
 				"name": "alt_bn128_pairing",
 				"pricing": {
 					"0": {
 						"price": { "alt_bn128_pairing": { "base": 100000, "pair": 80000 }}
 					},
-					"0x7fffffffffffff": {
+					"12598600": {
 						"info": "EIP 1108 transition",
 						"price": { "alt_bn128_pairing": { "base": 45000, "pair": 34000 }}
 					}
 				}
 			}
 		},
+		"0x0000000000000000000000000000000000000009": {
+			"builtin": {
+				"name": "blake2_f",
+				"pricing": {
+					"12598600": {
+						"info": "EIP 1108 transition",
+						"price": {
+							"blake2_f": {
+								"gas_per_round": 1
+							}
+						}
+					}
+				}
+			}
+		},
 		"0x0000000000000000000000000000000000000001": {
 			"balance": "1",
 			"builtin": {
 				"name": "ecrecover",
 				"pricing": {
-					"linear": {
-						"base": 3000,
-						"word": 0
+					"0": {
+						"price": {
+							"linear": {
+								"base": 3000,
+								"word": 0
+							}
+						}
 					}
 				}
 			}
@@ -118,9 +155,13 @@
 			"builtin": {
 				"name": "sha256",
 				"pricing": {
-					"linear": {
-						"base": 60,
-						"word": 12
+					"0": {
+						"price": {
+							"linear": {
+								"base": 60,
+								"word": 12
+							}
+						}
 					}
 				}
 			}
@@ -130,9 +171,13 @@
 			"builtin": {
 				"name": "ripemd160",
 				"pricing": {
-					"linear": {
-						"base": 600,
-						"word": 120
+					"0": {
+						"price": {
+							"linear": {
+								"base": 600,
+								"word": 120
+							}
+						}
 					}
 				}
 			}
@@ -142,9 +187,13 @@
 			"builtin": {
 				"name": "identity",
 				"pricing": {
-					"linear": {
-						"base": 15,
-						"word": 3
+					"0": {
+						"price": {
+							"linear": {
+								"base": 15,
+								"word": 3
+							}
+						}
 					}
 				}
 			}
diff --git a/ethcore/res/ethereum/poasokol.json b/ethcore/res/ethereum/poasokol.json
index db39c4654..31fb85c49 100644
--- a/ethcore/res/ethereum/poasokol.json
+++ b/ethcore/res/ethereum/poasokol.json
@@ -42,7 +42,12 @@
 		"eip1014Transition": 6464300,
 		"eip1052Transition": 6464300,
 		"eip1283Transition": 6464300,
-		"eip1283DisableTransition": 7026400
+		"eip1283DisableTransition": 7026400,
+		"eip1283ReenableTransition": 12095200,
+		"eip1344Transition": 12095200,
+		"eip1706Transition": 12095200,
+		"eip1884Transition": 12095200,
+		"eip2028Transition": 12095200
 	},
 	"genesis": {
 		"seal": {
@@ -55,6 +60,7 @@
 		"gasLimit": "0x663BE0"
 	},
 	"nodes": [
+		"enode://bdcd6f875583df2bd8094f08ae58c7c2db6ed67795ca8c0e6415a30721d3657291aec9b933d15e17e0b36ad7a76424a1447ddbfc75809a04f7a0ffef5617dd56@3.91.206.172:30303",
 		"enode://8e0af07c86ec36590bb6368e7ad0c45b6dc658f5fb66ec68889a614affddda5e021bd513bcf4fb2fae4a3bbe08cf0de84f037cd58478a89665dfce1ded2595c7@34.236.37.74:30303",
 		"enode://f1a5100a81cb73163ae450c584d06b1f644aa4fad4486c6aeb4c384b343c54bb66c744aa5f133af66ea1b25f0f4a454f04878f3e96ee4cd2390c047396d6357b@209.97.158.4:30303",
 		"enode://0d1e0372f63a3f0b82d66635ea101ecc0f6797788a078805cc933dd93e6a22f7c9fa51ab4e2d21da02d04480ef19f3bbb9a2b41dd1c262085d295a354bb8b0f9@18.217.47.209:30303",
@@ -64,7 +70,20 @@
 		"enode://b022ff70b5fcaf9596ae5efed99a8198b4ae0578ee9d17b733609d803a75cef95d3a2a18e50dca9a7c3b26139f158c59eaf8b5fb8d1d331c9a46934a78acabe8@206.189.76.128:30303"
 	],
 	"accounts": {
-		"0000000000000000000000000000000000000005": { "builtin": { "name": "modexp", "activate_at": "0x0", "pricing": { "modexp": { "divisor": 20 } } } },
+		"0000000000000000000000000000000000000005": {
+			"builtin": {
+				"name": "modexp",
+				"pricing": {
+					"0": {
+						"price": {
+							"modexp": {
+								"divisor": 20
+							}
+						}
+					}
+				}
+			}
+		},
 		"0000000000000000000000000000000000000006": {
 			"builtin": {
 				"name": "alt_bn128_add",
@@ -72,7 +91,7 @@
 					"0": {
 						"price": { "alt_bn128_const_operations": { "price": 500 }}
 					},
-					"0x7fffffffffffff": {
+					"12095200": {
 						"info": "EIP 1108 transition",
 						"price": { "alt_bn128_const_operations": { "price": 150 }}
 					}
@@ -86,7 +105,7 @@
 					"0": {
 						"price": { "alt_bn128_const_operations": { "price": 40000 }}
 					},
-					"0x7fffffffffffff": {
+					"12095200": {
 						"info": "EIP 1108 transition",
 						"price": { "alt_bn128_const_operations": { "price": 6000 }}
 					}
@@ -100,21 +119,40 @@
 					"0": {
 						"price": { "alt_bn128_pairing": { "base": 100000, "pair": 80000 }}
 					},
-					"0x7fffffffffffff": {
+					"12095200": {
 						"info": "EIP 1108 transition",
 						"price": { "alt_bn128_pairing": { "base": 45000, "pair": 34000 }}
 					}
 				}
 			}
 		},
+		"0x0000000000000000000000000000000000000009": {
+			"builtin": {
+				"name": "blake2_f",
+				"pricing": {
+					"12095200": {
+						"info": "EIP 1108 transition",
+						"price": {
+							"blake2_f": {
+								"gas_per_round": 1
+							}
+						}
+					}
+				}
+			}
+		},
 		"0x0000000000000000000000000000000000000001": {
 			"balance": "1",
 			"builtin": {
 				"name": "ecrecover",
 				"pricing": {
-					"linear": {
-						"base": 3000,
-						"word": 0
+					"0": {
+						"price": {
+							"linear": {
+								"base": 3000,
+								"word": 0
+							}
+						}
 					}
 				}
 			}
@@ -124,9 +162,13 @@
 			"builtin": {
 				"name": "sha256",
 				"pricing": {
-					"linear": {
-						"base": 60,
-						"word": 12
+					"0": {
+						"price": {
+							"linear": {
+								"base": 60,
+								"word": 12
+							}
+						}
 					}
 				}
 			}
@@ -136,9 +178,13 @@
 			"builtin": {
 				"name": "ripemd160",
 				"pricing": {
-					"linear": {
-						"base": 600,
-						"word": 120
+					"0": {
+						"price": {
+							"linear": {
+								"base": 600,
+								"word": 120
+							}
+						}
 					}
 				}
 			}
@@ -148,9 +194,13 @@
 			"builtin": {
 				"name": "identity",
 				"pricing": {
-					"linear": {
-						"base": 15,
-						"word": 3
+					"0": {
+						"price": {
+							"linear": {
+								"base": 15,
+								"word": 3
+							}
+						}
 					}
 				}
 			}
diff --git a/ethcore/res/ethereum/ropsten.json b/ethcore/res/ethereum/ropsten.json
index cd5352414..477512ec9 100644
--- a/ethcore/res/ethereum/ropsten.json
+++ b/ethcore/res/ethereum/ropsten.json
@@ -16,7 +16,8 @@
 				"eip100bTransition": "0x19f0a0",
 				"difficultyBombDelays": {
 					"0x19f0a0": "0x2dc6c0",
-					"0x408b70": "0x1e8480"
+					"0x408b70": "0x1e8480",
+					"0x6c993d": "0x3d0900"
 				}
 			}
 		}
diff --git a/ethcore/res/ethereum/xdai.json b/ethcore/res/ethereum/xdai.json
index ba224d980..2da25ca4e 100644
--- a/ethcore/res/ethereum/xdai.json
+++ b/ethcore/res/ethereum/xdai.json
@@ -37,6 +37,11 @@
 		"eip1052Transition": 1604400,
 		"eip1283Transition": 1604400,
 		"eip1283DisableTransition": 2508800,
+		"eip1283ReenableTransition": 7298030,
+		"eip1344Transition": 7298030,
+		"eip1706Transition": 7298030,
+		"eip1884Transition": 7298030,
+		"eip2028Transition": 7298030,
 		"registrar": "0x1ec97dc137f5168af053c24460a1200502e1a9d2"
 	},
 	"genesis": {
@@ -2865,10 +2870,13 @@
 		"0x0000000000000000000000000000000000000005": {
 			"builtin": {
 				"name": "modexp",
-				"activate_at": "0x0",
 				"pricing": {
-					"modexp": {
-						"divisor": 20
+					"0": {
+						"price": {
+							"modexp": {
+								"divisor": 20
+							}
+						}
 					}
 				}
 			}
@@ -2880,7 +2888,7 @@
 					"0": {
 						"price": { "alt_bn128_const_operations": { "price": 500 }}
 					},
-					"0x7fffffffffffff": {
+					"7298030": {
 						"info": "EIP 1108 transition",
 						"price": { "alt_bn128_const_operations": { "price": 150 }}
 					}
@@ -2894,7 +2902,7 @@
 					"0": {
 						"price": { "alt_bn128_const_operations": { "price": 40000 }}
 					},
-					"0x7fffffffffffff": {
+					"7298030": {
 						"info": "EIP 1108 transition",
 						"price": { "alt_bn128_const_operations": { "price": 6000 }}
 					}
@@ -2908,21 +2916,40 @@
 					"0": {
 						"price": { "alt_bn128_pairing": { "base": 100000, "pair": 80000 }}
 					},
-					"0x7fffffffffffff": {
+					"7298030": {
 						"info": "EIP 1108 transition",
 						"price": { "alt_bn128_pairing": { "base": 45000, "pair": 34000 }}
 					}
 				}
 			}
 		},
+		"0x0000000000000000000000000000000000000009": {
+			"builtin": {
+				"name": "blake2_f",
+				"pricing": {
+					"7298030": {
+						"info": "EIP 1108 transition",
+						"price": {
+							"blake2_f": {
+								"gas_per_round": 1
+							}
+						}
+					}
+				}
+			}
+		},
 		"0x0000000000000000000000000000000000000001": {
 			"balance": "1",
 			"builtin": {
 				"name": "ecrecover",
 				"pricing": {
-					"linear": {
-						"base": 3000,
-						"word": 0
+					"0": {
+						"price": {
+							"linear": {
+								"base": 3000,
+								"word": 0
+							}
+						}
 					}
 				}
 			}
@@ -2932,9 +2959,13 @@
 			"builtin": {
 				"name": "sha256",
 				"pricing": {
-					"linear": {
-						"base": 60,
-						"word": 12
+					"0": {
+						"price": {
+							"linear": {
+								"base": 60,
+								"word": 12
+							}
+						}
 					}
 				}
 			}
@@ -2944,9 +2975,13 @@
 			"builtin": {
 				"name": "ripemd160",
 				"pricing": {
-					"linear": {
-						"base": 600,
-						"word": 120
+					"0": {
+						"price": {
+							"linear": {
+								"base": 600,
+								"word": 120
+							}
+						}
 					}
 				}
 			}
@@ -2956,9 +2991,13 @@
 			"builtin": {
 				"name": "identity",
 				"pricing": {
-					"linear": {
-						"base": 15,
-						"word": 3
+					"0": {
+						"price": {
+							"linear": {
+								"base": 15,
+								"word": 3
+							}
+						}
 					}
 				}
 			}
diff --git a/ethcore/src/client/evm_test_client.rs b/ethcore/src/client/evm_test_client.rs
index d65e20691..be5857b0e 100644
--- a/ethcore/src/client/evm_test_client.rs
+++ b/ethcore/src/client/evm_test_client.rs
@@ -245,7 +245,7 @@ impl<'a> EvmTestClient<'a> {
 	) -> std::result::Result<TransactSuccess<T::Output, V::Output>, TransactErr> {
 		let initial_gas = transaction.gas;
 		// Verify transaction
-		let is_ok = transaction.verify_basic(true, None, false);
+		let is_ok = transaction.verify_basic(true, None);
 		if let Err(error) = is_ok {
 			return Err(
 				TransactErr{
diff --git a/ethcore/src/machine/impls.rs b/ethcore/src/machine/impls.rs
index fca611d4e..371d088d5 100644
--- a/ethcore/src/machine/impls.rs
+++ b/ethcore/src/machine/impls.rs
@@ -367,7 +367,7 @@ impl EthereumMachine {
 		} else {
 			None
 		};
-		t.verify_basic(check_low_s, chain_id, false)?;
+		t.verify_basic(check_low_s, chain_id)?;
 
 		Ok(())
 	}
diff --git a/ethcore/src/miner/miner.rs b/ethcore/src/miner/miner.rs
index 1da323e30..815aba6cf 100644
--- a/ethcore/src/miner/miner.rs
+++ b/ethcore/src/miner/miner.rs
@@ -1600,6 +1600,30 @@ mod tests {
 		assert_eq!(miner.prepare_pending_block(&client), BlockPreparationStatus::NotPrepared);
 	}
 
+	#[test]
+	fn should_reject_local_transaction_with_invalid_chain_id() {
+		let spec = Spec::new_test();
+		let miner = Miner::new_for_tests(&spec, None);
+		let client = TestBlockChainClient::default();
+		let chain_id = spec.chain_id();
+
+		// chain_id + 100500 is invalid
+		let import = miner.import_claimed_local_transaction(
+			&client,
+			PendingTransaction::new(transaction_with_chain_id(chain_id + 10500), None),
+			false,
+		);
+		assert_eq!(import, Err(transaction::Error::InvalidChainId));
+
+		// chain_id is valid
+		let import = miner.import_claimed_local_transaction(
+			&client,
+			PendingTransaction::new(transaction_with_chain_id(chain_id), None),
+			false,
+		);
+		assert_eq!(import, Ok(()));
+	}
+
 	#[test]
 	fn should_prioritize_locals() {
 		let client = TestBlockChainClient::default();
diff --git a/ethcore/src/miner/pool_client.rs b/ethcore/src/miner/pool_client.rs
index 93cc0e8cf..e6ff3a329 100644
--- a/ethcore/src/miner/pool_client.rs
+++ b/ethcore/src/miner/pool_client.rs
@@ -136,7 +136,12 @@ impl<'a, C: 'a> pool::client::Client for PoolClient<'a, C> where
 		self.chain.transaction_block(TransactionId::Hash(*hash)).is_some()
 	}
 
-	fn verify_transaction(&self, tx: UnverifiedTransaction)-> Result<SignedTransaction, transaction::Error> {
+	fn verify_transaction_basic(&self, tx: &UnverifiedTransaction) -> Result<(), transaction::Error> {
+		self.engine.verify_transaction_basic(tx, &self.best_block_header)?;
+		Ok(())
+	}
+
+	fn verify_transaction(&self, tx: UnverifiedTransaction) -> Result<SignedTransaction, transaction::Error> {
 		self.engine.verify_transaction_basic(&tx, &self.best_block_header)?;
 		let tx = self.engine.verify_transaction_unordered(tx, &self.best_block_header)?;
 
diff --git a/ethcore/types/src/transaction/transaction.rs b/ethcore/types/src/transaction/transaction.rs
index 439880089..8153142eb 100644
--- a/ethcore/types/src/transaction/transaction.rs
+++ b/ethcore/types/src/transaction/transaction.rs
@@ -143,6 +143,7 @@ impl HeapSizeOf for Transaction {
 	}
 }
 
+#[cfg(any(test, feature = "test-helpers"))]
 impl From<ethjson::state::Transaction> for SignedTransaction {
 	fn from(t: ethjson::state::Transaction) -> Self {
 		let to: Option<ethjson::hash::Address> = t.to.into();
@@ -242,7 +243,10 @@ impl Transaction {
 		}
 	}
 
-	/// Add EIP-86 compatible empty signature.
+	/// Legacy EIP-86 compatible empty signature.
+	/// This method is used in json tests as well as
+	/// signature verification tests.
+	#[cfg(any(test, feature = "test-helpers"))]
 	pub fn null_sign(self, chain_id: u64) -> SignedTransaction {
 		SignedTransaction {
 			transaction: UnverifiedTransaction {
@@ -306,7 +310,7 @@ impl rlp::Decodable for UnverifiedTransaction {
 			v: d.val_at(6)?,
 			r: d.val_at(7)?,
 			s: d.val_at(8)?,
-			hash: hash,
+			hash,
 		})
 	}
 }
@@ -323,7 +327,7 @@ impl UnverifiedTransaction {
 		self
 	}
 
-	/// Checks is signature is empty.
+	/// Checks if the signature is empty.
 	pub fn is_unsigned(&self) -> bool {
 		self.r.is_zero() && self.s.is_zero()
 	}
@@ -387,17 +391,12 @@ impl UnverifiedTransaction {
 	}
 
 	/// Verify basic signature params. Does not attempt sender recovery.
-	pub fn verify_basic(&self, check_low_s: bool, chain_id: Option<u64>, allow_empty_signature: bool) -> Result<(), error::Error> {
-		if check_low_s && !(allow_empty_signature && self.is_unsigned()) {
-			self.check_low_s()?;
-		}
-		// Disallow unsigned transactions in case EIP-86 is disabled.
-		if !allow_empty_signature && self.is_unsigned() {
+	pub fn verify_basic(&self, check_low_s: bool, chain_id: Option<u64>) -> Result<(), error::Error> {
+		if self.is_unsigned() {
 			return Err(ethkey::Error::InvalidSignature.into());
 		}
-		// EIP-86: Transactions of this form MUST have gasprice = 0, nonce = 0, value = 0, and do NOT increment the nonce of account 0.
-		if allow_empty_signature && self.is_unsigned() && !(self.gas_price.is_zero() && self.value.is_zero() && self.nonce.is_zero()) {
-			return Err(ethkey::Error::InvalidSignature.into())
+		if check_low_s {
+			self.check_low_s()?;
 		}
 		match (self.chain_id(), chain_id) {
 			(None, _) => {},
@@ -443,20 +442,15 @@ impl SignedTransaction {
 	/// Try to verify transaction and recover sender.
 	pub fn new(transaction: UnverifiedTransaction) -> Result<Self, ethkey::Error> {
 		if transaction.is_unsigned() {
-			Ok(SignedTransaction {
-				transaction: transaction,
-				sender: UNSIGNED_SENDER,
-				public: None,
-			})
-		} else {
-			let public = transaction.recover_public()?;
-			let sender = public_to_address(&public);
-			Ok(SignedTransaction {
-				transaction: transaction,
-				sender: sender,
-				public: Some(public),
-			})
+			return Err(ethkey::Error::InvalidSignature);
 		}
+		let public = transaction.recover_public()?;
+		let sender = public_to_address(&public);
+		Ok(SignedTransaction {
+			transaction,
+			sender,
+			public: Some(public),
+		})
 	}
 
 	/// Returns transaction sender.
@@ -646,6 +640,25 @@ mod tests {
 		assert_eq!(t.chain_id(), None);
 	}
 
+	#[test]
+	fn should_reject_null_signature() {
+		use std::str::FromStr;
+		let t = Transaction {
+			nonce: U256::zero(),
+			gas_price: U256::from(10000000000u64),
+			gas: U256::from(21000),
+			action: Action::Call(Address::from_str("d46e8dd67c5d32be8058bb8eb970870f07244567").unwrap()),
+			value: U256::from(1),
+			data: vec![]
+		}.null_sign(1);
+
+		let res = SignedTransaction::new(t.transaction);
+		match res {
+			Err(ethkey::Error::InvalidSignature) => {}
+			_ => panic!("null signature should be rejected"),
+		}
+	}
+
 	#[test]
 	fn should_recover_from_chain_specific_signing() {
 		use ethkey::{Random, Generator};
diff --git a/evmbin/Cargo.toml b/evmbin/Cargo.toml
index 7605132ef..626b13150 100644
--- a/evmbin/Cargo.toml
+++ b/evmbin/Cargo.toml
@@ -9,7 +9,7 @@ name = "parity-evm"
 path = "./src/main.rs"
 
 [dependencies]
-common-types = { path = "../ethcore/types" }
+common-types = { path = "../ethcore/types", features = ["test-helpers"] }
 docopt = "1.0"
 env_logger = "0.5"
 ethcore = { path = "../ethcore", features = ["test-helpers", "json-tests", "to-pod-full"] }
diff --git a/json/src/spec/builtin.rs b/json/src/spec/builtin.rs
index 19ddfc2c6..77b5bcce6 100644
--- a/json/src/spec/builtin.rs
+++ b/json/src/spec/builtin.rs
@@ -203,6 +203,28 @@ mod tests {
 		]);
 	}
 
+	#[test]
+	fn deserialization_alt_bn128_const_operations() {
+		let s = r#"{
+			"name": "alt_bn128_mul",
+			"pricing": {
+				"100500": {
+					"price": { "alt_bn128_const_operations": { "price": 123 }}
+				}
+			}
+		}"#;
+		let builtin: Builtin = serde_json::from_str::<BuiltinCompat>(s).unwrap().into();
+		assert_eq!(builtin.name, "alt_bn128_mul");
+		assert_eq!(builtin.pricing, map![
+			100500 => PricingAt {
+				info: None,
+				price: Pricing::AltBn128ConstOperations(AltBn128ConstOperations { 
+					price: 123,
+				}),
+			}
+		]);
+	}
+
 	#[test]
 	fn activate_at() {
 		let s = r#"{
diff --git a/json/src/uint.rs b/json/src/uint.rs
index 3f1d02f03..4b9ccec6f 100644
--- a/json/src/uint.rs
+++ b/json/src/uint.rs
@@ -97,6 +97,7 @@ impl<'a> Visitor<'a> for UintVisitor {
 	}
 }
 
+/// Deserialize and validate that the value is non-zero
 pub fn validate_non_zero<'de, D>(d: D) -> Result<Uint, D::Error> where D: Deserializer<'de> {
 	let value = Uint::deserialize(d)?;
 
@@ -107,6 +108,7 @@ pub fn validate_non_zero<'de, D>(d: D) -> Result<Uint, D::Error> where D: Deseri
 	Ok(value)
 }
 
+/// Deserialize and validate that the value is non-zero
 pub fn validate_optional_non_zero<'de, D>(d: D) -> Result<Option<Uint>, D::Error> where D: Deserializer<'de> {
 	let value: Option<Uint> = Option::deserialize(d)?;
 
diff --git a/miner/src/pool/client.rs b/miner/src/pool/client.rs
index bcd2b9689..1579ba40d 100644
--- a/miner/src/pool/client.rs
+++ b/miner/src/pool/client.rs
@@ -50,6 +50,15 @@ pub trait Client: fmt::Debug + Sync {
 	/// Is transaction with given hash already in the blockchain?
 	fn transaction_already_included(&self, hash: &H256) -> bool;
 
+	/// Perform basic/cheap transaction verification.
+	///
+	/// This should include all cheap checks that can be done before
+	/// actually checking the signature, like chain-replay protection.
+	///
+	/// This method is currently used only for verifying local transactions.
+	fn verify_transaction_basic(&self, t: &transaction::UnverifiedTransaction)
+		-> Result<(), transaction::Error>;
+
 	/// Structurarily verify given transaction.
 	fn verify_transaction(&self, tx: transaction::UnverifiedTransaction)
 		-> Result<transaction::SignedTransaction, transaction::Error>;
diff --git a/miner/src/pool/tests/client.rs b/miner/src/pool/tests/client.rs
index 4735fbd64..ce927c8e9 100644
--- a/miner/src/pool/tests/client.rs
+++ b/miner/src/pool/tests/client.rs
@@ -103,6 +103,12 @@ impl pool::client::Client for TestClient {
 		false
 	}
 
+	fn verify_transaction_basic(&self, _tx: &UnverifiedTransaction)
+		-> Result<(), transaction::Error>
+	{
+		Ok(())
+	}
+
 	fn verify_transaction(&self, tx: UnverifiedTransaction)
 		-> Result<SignedTransaction, transaction::Error>
 	{
diff --git a/miner/src/pool/verifier.rs b/miner/src/pool/verifier.rs
index 51232e967..bd4b50e73 100644
--- a/miner/src/pool/verifier.rs
+++ b/miner/src/pool/verifier.rs
@@ -250,7 +250,13 @@ impl<C: Client> txpool::Verifier<Transaction> for Verifier<C, ::pool::scoring::N
 					bail!(err)
 				},
 			},
-			Transaction::Local(tx) => tx,
+			Transaction::Local(tx) => match self.client.verify_transaction_basic(&**tx) {
+				Ok(()) => tx,
+				Err(err) => {
+					warn!(target: "txqueue", "[{:?}] Rejected local tx {:?}", hash, err);
+					return Err(err)
+				}
+			},
 		};
 
 		// Verify RLP payload
diff --git a/util/version/Cargo.toml b/util/version/Cargo.toml
index fb8449d5b..7a8e32cc8 100644
--- a/util/version/Cargo.toml
+++ b/util/version/Cargo.toml
@@ -3,7 +3,7 @@
 [package]
 name = "parity-version"
 # NOTE: this value is used for Parity Ethereum version string (via env CARGO_PKG_VERSION)
-version = "2.5.11"
+version = "2.5.12"
 authors = ["Parity Technologies <admin@parity.io>"]
 build = "build.rs"