diff --git a/CHANGELOG.md b/CHANGELOG.md
index 1c0853001..e7e509611 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -1,3 +1,8 @@
+## OpenEthereum v3.3.0-rc.12
+
+Enhancements:
+* London hardfork block: xDai (19040000)
+
 ## OpenEthereum v3.3.0-rc.11
 
 Bug fixes:
diff --git a/Cargo.lock b/Cargo.lock
index d82803b5a..52357b08a 100644
--- a/Cargo.lock
+++ b/Cargo.lock
@@ -2932,7 +2932,7 @@ checksum = "2839e79665f131bdb5782e51f2c6c9599c133c6098982a54c794358bf432529c"
 
 [[package]]
 name = "openethereum"
-version = "3.3.0-rc.11"
+version = "3.3.0-rc.12"
 dependencies = [
  "ansi_term 0.10.2",
  "atty",
@@ -3282,7 +3282,7 @@ dependencies = [
 
 [[package]]
 name = "parity-version"
-version = "3.3.0-rc.11"
+version = "3.3.0-rc.12"
 dependencies = [
  "parity-bytes",
  "rlp",
diff --git a/Cargo.toml b/Cargo.toml
index 4a9e1a624..e2c01499b 100644
--- a/Cargo.toml
+++ b/Cargo.toml
@@ -2,7 +2,7 @@
 description = "OpenEthereum"
 name = "openethereum"
 # NOTE Make sure to update util/version/Cargo.toml as well
-version = "3.3.0-rc.11"
+version = "3.3.0-rc.12"
 license = "GPL-3.0"
 authors = [
 	"OpenEthereum developers",
diff --git a/crates/ethcore/res/chainspec/xdai.json b/crates/ethcore/res/chainspec/xdai.json
index 72111749a..40194e42f 100644
--- a/crates/ethcore/res/chainspec/xdai.json
+++ b/crates/ethcore/res/chainspec/xdai.json
@@ -56,6 +56,15 @@
 		"eip2028Transition": 7298030,
 		"eip2929Transition": 16101500,
 		"eip2930Transition": 16101500,
+		"eip3198Transition": 19040000,
+		"eip3529Transition": 19040000,
+		"eip3541Transition": 19040000,
+		"eip1559Transition": 19040000,
+		"eip1559BaseFeeMaxChangeDenominator": "0x8",
+		"eip1559ElasticityMultiplier": "0x2",
+		"eip1559BaseFeeInitialValue": "0x3b9aca00",
+		"eip1559FeeCollector": "0x6BBe78ee9e474842Dbd4AB4987b3CeFE88426A92",
+		"eip1559FeeCollectorTransition": 19040000,
 		"registrar": "0x6B53721D4f2Fb9514B85f5C49b197D857e36Cf03",
 		"transactionPermissionContract": "0x7Dd7032AA75A37ea0b150f57F899119C7379A78b",
 		"transactionPermissionContractTransition": 9186425
diff --git a/crates/util/version/Cargo.toml b/crates/util/version/Cargo.toml
index 8e024c6f1..38649c7be 100644
--- a/crates/util/version/Cargo.toml
+++ b/crates/util/version/Cargo.toml
@@ -1,7 +1,7 @@
 [package]
 name = "parity-version"
 # NOTE: this value is used for OpenEthereum version string (via env CARGO_PKG_VERSION)
-version = "3.3.0-rc.11"
+version = "3.3.0-rc.12"
 authors = ["Parity Technologies <admin@parity.io>"]
 build = "build.rs"