diff --git a/defs/coins/crown.json b/defs/coins/crown.json
new file mode 100644
index 000000000..225c425f5
--- /dev/null
+++ b/defs/coins/crown.json
@@ -0,0 +1,33 @@
+{
+	"coin_name": "Crown",
+	"coin_shortcut": "CRW",
+	"coin_label": "Crown",
+	"curve_name": "secp256k1",
+	"address_type": 0,
+	"address_type_p2sh": 28,
+	"maxfee_kb": 2000000,
+	"minfee_kb": 1000,
+	"signed_message_header": "Crown Signed Message:\n",
+	"hash_genesis_block": "0000000085370d5e122f64f4ab19c68614ff3df78c8d13cb814fd7e69a1dc6da",
+	"xprv_magic": "0488ade4",
+	"xpub_magic": "0488b21e",
+	"xpub_magic_segwit_p2sh": null,
+	"bech32_prefix": null,
+	"bip44": 72,
+	"segwit": false,
+	"decred": false,
+	"forkid": null,
+	"force_bip143": false,
+	"default_fee_b": {
+		"Normal": 10
+	},
+	"dust_limit": 546,
+	"blocktime_minutes": 1,
+	"address_prefix": "crown:",
+	"min_address_length": 27,
+	"max_address_length": 34,
+	"bitcore": [
+		"https://crw-bitcore.crown.tech/",
+		"https://crw2-bitcore.crown.tech/"
+	]
+}
diff --git a/defs/coins/flashcoin.json b/defs/coins/flashcoin.json
new file mode 100644
index 000000000..0f032d107
--- /dev/null
+++ b/defs/coins/flashcoin.json
@@ -0,0 +1,34 @@
+{
+	"coin_name": "Flashcoin",
+	"coin_shortcut": "FLASH",
+	"coin_label": "Flashcoin",
+	"curve_name": "secp256k1",
+	"address_type": 68,
+	"address_type_p2sh": 130,
+	"maxfee_kb": 4000000,
+	"minfee_kb": 1000,
+	"signed_message_header": "Flashcoin Signed Message:\n",
+	"hash_genesis_block": "aa0cf4f5ce0a3c550ce5674c1e808c417cf5077b4e95bda1d6fbaeaf4258972b",
+	"xprv_magic": "0488ade4",
+	"xpub_magic": "0488b21e",
+	"xpub_magic_segwit_p2sh": "049d7cb2",
+	"bech32_prefix": null,
+	"cashaddr_prefix": null,
+	"bip44": 120,
+	"segwit": true,
+	"decred": false,
+	"forkid": null,
+	"force_bip143": false,
+	"default_fee_b": {
+		"Normal": 0
+	},
+	"dust_limit": 10000,
+	"blocktime_minutes": 1,
+	"firmware": "stable",
+	"address_prefix": "flashcoin:",
+	"min_address_length": 27,
+	"max_address_length": 34,
+	"bitcore": [
+		"https://explorer.flashcoin.io"
+	]
+}
diff --git a/defs/coins/myriad.json b/defs/coins/myriad.json
new file mode 100644
index 000000000..0cee3d94e
--- /dev/null
+++ b/defs/coins/myriad.json
@@ -0,0 +1,34 @@
+{
+	"coin_name": "Myriad",
+	"coin_shortcut": "XMY",
+	"coin_label": "Myriad",
+	"curve_name": "secp256k1",
+	"address_type": 50,
+	"address_type_p2sh": 9,
+	"maxfee_kb": 2000000,
+	"minfee_kb": 1000,
+	"signed_message_header": "Myriadcoin Signed Message:\n",
+	"hash_genesis_block": "00000ffde4c020b5938441a0ea3d314bf619eff0b38f32f78f7583cffa1ea485",
+	"xprv_magic": "0488ade4",
+	"xpub_magic": "0488b21e",
+	"xpub_magic_segwit_p2sh": null,
+	"bech32_prefix": null,
+	"bip44": 90,
+	"segwit": true,
+	"decred": false,
+	"forkid": null,
+	"force_bip143": false,
+	"default_fee_b": {
+		"Low": 10,
+		"Economy": 70,
+		"Normal": 140,
+		"High": 200
+	},
+	"dust_limit": 546,
+	"blocktime_minutes": 1,
+	"firmware": "stable",
+	"address_prefix": "myriadcoin:",
+	"min_address_length": 27,
+	"max_address_length": 34,
+	"bitcore": []
+}