diff --git a/matrix-sdk-android/src/main/java/im/vector/matrix/android/api/session/room/model/message/MessageVerificationAcceptContent.kt b/matrix-sdk-android/src/main/java/im/vector/matrix/android/api/session/room/model/message/MessageVerificationAcceptContent.kt
index d4fb3a44fd1..454110ed198 100644
--- a/matrix-sdk-android/src/main/java/im/vector/matrix/android/api/session/room/model/message/MessageVerificationAcceptContent.kt
+++ b/matrix-sdk-android/src/main/java/im/vector/matrix/android/api/session/room/model/message/MessageVerificationAcceptContent.kt
@@ -37,19 +37,6 @@ internal data class MessageVerificationAcceptContent(
     override val transactionID: String?
         get() = relatesTo?.eventId
 
-    override fun isValid(): Boolean {
-        if (transactionID.isNullOrBlank()
-                || keyAgreementProtocol.isNullOrBlank()
-                || hash.isNullOrBlank()
-                || commitment.isNullOrBlank()
-                || messageAuthenticationCode.isNullOrBlank()
-                || shortAuthenticationStrings.isNullOrEmpty()) {
-            Timber.e("## received invalid verification request")
-            return false
-        }
-        return true
-    }
-
     override fun toEventContent() = toContent()
 
     companion object : VerificationInfoAcceptFactory {
diff --git a/matrix-sdk-android/src/main/java/im/vector/matrix/android/api/session/room/model/message/MessageVerificationCancelContent.kt b/matrix-sdk-android/src/main/java/im/vector/matrix/android/api/session/room/model/message/MessageVerificationCancelContent.kt
index 9b7ca13df80..5cfef097c15 100644
--- a/matrix-sdk-android/src/main/java/im/vector/matrix/android/api/session/room/model/message/MessageVerificationCancelContent.kt
+++ b/matrix-sdk-android/src/main/java/im/vector/matrix/android/api/session/room/model/message/MessageVerificationCancelContent.kt
@@ -28,7 +28,6 @@ data class MessageVerificationCancelContent(
         @Json(name = "code") override val code: String? = null,
         @Json(name = "reason") override val reason: String? = null,
         @Json(name = "m.relates_to") val relatesTo: RelationDefaultContent?
-
 ) : VerificationInfoCancel {
 
     override val transactionID: String?
@@ -36,13 +35,6 @@ data class MessageVerificationCancelContent(
 
     override fun toEventContent() = toContent()
 
-    override fun isValid(): Boolean {
-        if (transactionID.isNullOrBlank() || code.isNullOrBlank()) {
-            return false
-        }
-        return true
-    }
-
     companion object {
         fun create(transactionId: String, reason: CancelCode): MessageVerificationCancelContent {
             return MessageVerificationCancelContent(
diff --git a/matrix-sdk-android/src/main/java/im/vector/matrix/android/api/session/room/model/message/MessageVerificationDoneContent.kt b/matrix-sdk-android/src/main/java/im/vector/matrix/android/api/session/room/model/message/MessageVerificationDoneContent.kt
index 224c5c52d30..d884bc16201 100644
--- a/matrix-sdk-android/src/main/java/im/vector/matrix/android/api/session/room/model/message/MessageVerificationDoneContent.kt
+++ b/matrix-sdk-android/src/main/java/im/vector/matrix/android/api/session/room/model/message/MessageVerificationDoneContent.kt
@@ -25,12 +25,20 @@ import im.vector.matrix.android.internal.crypto.verification.VerificationInfo
 @JsonClass(generateAdapter = true)
 internal data class MessageVerificationDoneContent(
         @Json(name = "m.relates_to") val relatesTo: RelationDefaultContent?
-) : VerificationInfo {
+) : VerificationInfo<ValidVerificationDone> {
 
     override val transactionID: String?
         get() = relatesTo?.eventId
 
-    override fun isValid() = transactionID?.isNotEmpty() == true
-
     override fun toEventContent(): Content? = toContent()
+
+    override fun asValidObject(): ValidVerificationDone? {
+        if (transactionID.isNullOrEmpty()) {
+            return null
+        }
+
+        return ValidVerificationDone
+    }
 }
+
+internal object ValidVerificationDone
diff --git a/matrix-sdk-android/src/main/java/im/vector/matrix/android/api/session/room/model/message/MessageVerificationKeyContent.kt b/matrix-sdk-android/src/main/java/im/vector/matrix/android/api/session/room/model/message/MessageVerificationKeyContent.kt
index 777e0e73188..7a4b95f3390 100644
--- a/matrix-sdk-android/src/main/java/im/vector/matrix/android/api/session/room/model/message/MessageVerificationKeyContent.kt
+++ b/matrix-sdk-android/src/main/java/im/vector/matrix/android/api/session/room/model/message/MessageVerificationKeyContent.kt
@@ -22,7 +22,6 @@ import im.vector.matrix.android.api.session.events.model.toContent
 import im.vector.matrix.android.api.session.room.model.relation.RelationDefaultContent
 import im.vector.matrix.android.internal.crypto.verification.VerificationInfoKey
 import im.vector.matrix.android.internal.crypto.verification.VerificationInfoKeyFactory
-import timber.log.Timber
 
 @JsonClass(generateAdapter = true)
 internal data class MessageVerificationKeyContent(
@@ -36,14 +35,6 @@ internal data class MessageVerificationKeyContent(
     override val transactionID: String?
         get() = relatesTo?.eventId
 
-    override fun isValid(): Boolean {
-        if (transactionID.isNullOrBlank() || key.isNullOrBlank()) {
-            Timber.e("## received invalid verification request")
-            return false
-        }
-        return true
-    }
-
     override fun toEventContent() = toContent()
 
     companion object : VerificationInfoKeyFactory {
diff --git a/matrix-sdk-android/src/main/java/im/vector/matrix/android/api/session/room/model/message/MessageVerificationMacContent.kt b/matrix-sdk-android/src/main/java/im/vector/matrix/android/api/session/room/model/message/MessageVerificationMacContent.kt
index 05e614dee97..1d732bf605a 100644
--- a/matrix-sdk-android/src/main/java/im/vector/matrix/android/api/session/room/model/message/MessageVerificationMacContent.kt
+++ b/matrix-sdk-android/src/main/java/im/vector/matrix/android/api/session/room/model/message/MessageVerificationMacContent.kt
@@ -35,13 +35,6 @@ internal data class MessageVerificationMacContent(
 
     override fun toEventContent() = toContent()
 
-    override fun isValid(): Boolean {
-        if (transactionID.isNullOrBlank() || keys.isNullOrBlank() || mac.isNullOrEmpty()) {
-            return false
-        }
-        return true
-    }
-
     companion object : VerificationInfoMacFactory {
         override fun create(tid: String, mac: Map<String, String>, keys: String): VerificationInfoMac {
             return MessageVerificationMacContent(
diff --git a/matrix-sdk-android/src/main/java/im/vector/matrix/android/api/session/room/model/message/MessageVerificationReadyContent.kt b/matrix-sdk-android/src/main/java/im/vector/matrix/android/api/session/room/model/message/MessageVerificationReadyContent.kt
index 4e237ba1c9a..d4b7e728ab1 100644
--- a/matrix-sdk-android/src/main/java/im/vector/matrix/android/api/session/room/model/message/MessageVerificationReadyContent.kt
+++ b/matrix-sdk-android/src/main/java/im/vector/matrix/android/api/session/room/model/message/MessageVerificationReadyContent.kt
@@ -35,13 +35,6 @@ internal data class MessageVerificationReadyContent(
 
     override fun toEventContent() = toContent()
 
-    override fun isValid(): Boolean {
-        if (transactionID.isNullOrBlank() || methods.isNullOrEmpty() || fromDevice.isNullOrEmpty()) {
-            return false
-        }
-        return true
-    }
-
     companion object : MessageVerificationReadyFactory {
         override fun create(tid: String, methods: List<String>, fromDevice: String): VerificationInfoReady {
             return MessageVerificationReadyContent(
diff --git a/matrix-sdk-android/src/main/java/im/vector/matrix/android/api/session/room/model/message/MessageVerificationRequestContent.kt b/matrix-sdk-android/src/main/java/im/vector/matrix/android/api/session/room/model/message/MessageVerificationRequestContent.kt
index 2ef4979f9d5..d19f938f45e 100644
--- a/matrix-sdk-android/src/main/java/im/vector/matrix/android/api/session/room/model/message/MessageVerificationRequestContent.kt
+++ b/matrix-sdk-android/src/main/java/im/vector/matrix/android/api/session/room/model/message/MessageVerificationRequestContent.kt
@@ -36,13 +36,6 @@ data class MessageVerificationRequestContent(
         @Json(name = "m.new_content") override val newContent: Content? = null
 ) : MessageContent, VerificationInfoRequest {
 
-    override fun isValid(): Boolean {
-        if (transactionID.isNullOrBlank() || methods.isNullOrEmpty() || fromDevice.isNullOrEmpty()) {
-            return false
-        }
-        return true
-    }
-
     override val transactionID: String?
         get() = relatesTo?.eventId
 
diff --git a/matrix-sdk-android/src/main/java/im/vector/matrix/android/internal/crypto/model/rest/KeyVerificationAccept.kt b/matrix-sdk-android/src/main/java/im/vector/matrix/android/internal/crypto/model/rest/KeyVerificationAccept.kt
index dc6075ca439..757b504db21 100644
--- a/matrix-sdk-android/src/main/java/im/vector/matrix/android/internal/crypto/model/rest/KeyVerificationAccept.kt
+++ b/matrix-sdk-android/src/main/java/im/vector/matrix/android/internal/crypto/model/rest/KeyVerificationAccept.kt
@@ -67,19 +67,6 @@ internal data class KeyVerificationAccept(
         override var commitment: String? = null
 ) : SendToDeviceObject, VerificationInfoAccept {
 
-    override fun isValid(): Boolean {
-        if (transactionID.isNullOrBlank()
-                || keyAgreementProtocol.isNullOrBlank()
-                || hash.isNullOrBlank()
-                || commitment.isNullOrBlank()
-                || messageAuthenticationCode.isNullOrBlank()
-                || shortAuthenticationStrings.isNullOrEmpty()) {
-            Timber.e("## received invalid verification request")
-            return false
-        }
-        return true
-    }
-
     override fun toSendToDeviceObject() = this
 
     companion object : VerificationInfoAcceptFactory {
diff --git a/matrix-sdk-android/src/main/java/im/vector/matrix/android/internal/crypto/model/rest/KeyVerificationCancel.kt b/matrix-sdk-android/src/main/java/im/vector/matrix/android/internal/crypto/model/rest/KeyVerificationCancel.kt
index dcf08531c80..6f940fd3285 100644
--- a/matrix-sdk-android/src/main/java/im/vector/matrix/android/internal/crypto/model/rest/KeyVerificationCancel.kt
+++ b/matrix-sdk-android/src/main/java/im/vector/matrix/android/internal/crypto/model/rest/KeyVerificationCancel.kt
@@ -53,11 +53,4 @@ internal data class KeyVerificationCancel(
     }
 
     override fun toSendToDeviceObject() = this
-
-    override fun isValid(): Boolean {
-        if (transactionID.isNullOrBlank() || code.isNullOrBlank()) {
-            return false
-        }
-        return true
-    }
 }
diff --git a/matrix-sdk-android/src/main/java/im/vector/matrix/android/internal/crypto/model/rest/KeyVerificationDone.kt b/matrix-sdk-android/src/main/java/im/vector/matrix/android/internal/crypto/model/rest/KeyVerificationDone.kt
index bdce77b31d5..eaaf8b82813 100644
--- a/matrix-sdk-android/src/main/java/im/vector/matrix/android/internal/crypto/model/rest/KeyVerificationDone.kt
+++ b/matrix-sdk-android/src/main/java/im/vector/matrix/android/internal/crypto/model/rest/KeyVerificationDone.kt
@@ -28,11 +28,4 @@ internal data class KeyVerificationDone(
 ) : SendToDeviceObject, VerificationInfoDone {
 
     override fun toSendToDeviceObject() = this
-
-    override fun isValid(): Boolean {
-        if (transactionID.isNullOrBlank()) {
-            return false
-        }
-        return true
-    }
 }
diff --git a/matrix-sdk-android/src/main/java/im/vector/matrix/android/internal/crypto/model/rest/KeyVerificationKey.kt b/matrix-sdk-android/src/main/java/im/vector/matrix/android/internal/crypto/model/rest/KeyVerificationKey.kt
index 4f90f8db8c9..a3baed85588 100644
--- a/matrix-sdk-android/src/main/java/im/vector/matrix/android/internal/crypto/model/rest/KeyVerificationKey.kt
+++ b/matrix-sdk-android/src/main/java/im/vector/matrix/android/internal/crypto/model/rest/KeyVerificationKey.kt
@@ -44,11 +44,4 @@ internal data class KeyVerificationKey(
     }
 
     override fun toSendToDeviceObject() = this
-
-    override fun isValid(): Boolean {
-        if (transactionID.isNullOrBlank() || key.isNullOrBlank()) {
-            return false
-        }
-        return true
-    }
 }
diff --git a/matrix-sdk-android/src/main/java/im/vector/matrix/android/internal/crypto/model/rest/KeyVerificationMac.kt b/matrix-sdk-android/src/main/java/im/vector/matrix/android/internal/crypto/model/rest/KeyVerificationMac.kt
index d6e712e0565..a72a7cbc64a 100644
--- a/matrix-sdk-android/src/main/java/im/vector/matrix/android/internal/crypto/model/rest/KeyVerificationMac.kt
+++ b/matrix-sdk-android/src/main/java/im/vector/matrix/android/internal/crypto/model/rest/KeyVerificationMac.kt
@@ -31,13 +31,6 @@ internal data class KeyVerificationMac(
 
 ) : SendToDeviceObject, VerificationInfoMac {
 
-    override fun isValid(): Boolean {
-        if (transactionID.isNullOrBlank() || keys.isNullOrBlank() || mac.isNullOrEmpty()) {
-            return false
-        }
-        return true
-    }
-
     override fun toSendToDeviceObject(): SendToDeviceObject? = this
 
     companion object : VerificationInfoMacFactory {
diff --git a/matrix-sdk-android/src/main/java/im/vector/matrix/android/internal/crypto/model/rest/KeyVerificationReady.kt b/matrix-sdk-android/src/main/java/im/vector/matrix/android/internal/crypto/model/rest/KeyVerificationReady.kt
index 004477e90b1..9050cbd9086 100644
--- a/matrix-sdk-android/src/main/java/im/vector/matrix/android/internal/crypto/model/rest/KeyVerificationReady.kt
+++ b/matrix-sdk-android/src/main/java/im/vector/matrix/android/internal/crypto/model/rest/KeyVerificationReady.kt
@@ -30,8 +30,4 @@ internal data class KeyVerificationReady(
 ) : SendToDeviceObject, VerificationInfoReady {
 
     override fun toSendToDeviceObject() = this
-
-    override fun isValid(): Boolean {
-        return !transactionID.isNullOrBlank() && !fromDevice.isNullOrBlank() && !methods.isNullOrEmpty()
-    }
 }
diff --git a/matrix-sdk-android/src/main/java/im/vector/matrix/android/internal/crypto/model/rest/KeyVerificationRequest.kt b/matrix-sdk-android/src/main/java/im/vector/matrix/android/internal/crypto/model/rest/KeyVerificationRequest.kt
index fcddb5c3d48..5aeeb8e85d4 100644
--- a/matrix-sdk-android/src/main/java/im/vector/matrix/android/internal/crypto/model/rest/KeyVerificationRequest.kt
+++ b/matrix-sdk-android/src/main/java/im/vector/matrix/android/internal/crypto/model/rest/KeyVerificationRequest.kt
@@ -32,11 +32,4 @@ internal data class KeyVerificationRequest(
 ) : SendToDeviceObject, VerificationInfoRequest {
 
     override fun toSendToDeviceObject() = this
-
-    override fun isValid(): Boolean {
-        if (transactionID.isNullOrBlank() || methods.isNullOrEmpty() || fromDevice.isNullOrEmpty()) {
-            return false
-        }
-        return true
-    }
 }
diff --git a/matrix-sdk-android/src/main/java/im/vector/matrix/android/internal/crypto/verification/VerificationInfo.kt b/matrix-sdk-android/src/main/java/im/vector/matrix/android/internal/crypto/verification/VerificationInfo.kt
index ed2e5dfbe0e..8f01bdd14af 100644
--- a/matrix-sdk-android/src/main/java/im/vector/matrix/android/internal/crypto/verification/VerificationInfo.kt
+++ b/matrix-sdk-android/src/main/java/im/vector/matrix/android/internal/crypto/verification/VerificationInfo.kt
@@ -18,10 +18,11 @@ package im.vector.matrix.android.internal.crypto.verification
 import im.vector.matrix.android.api.session.events.model.Content
 import im.vector.matrix.android.internal.crypto.model.rest.SendToDeviceObject
 
-interface VerificationInfo {
+interface VerificationInfo<ValidObject> {
     fun toEventContent(): Content? = null
     fun toSendToDeviceObject(): SendToDeviceObject? = null
-    fun isValid(): Boolean
+
+    fun asValidObject(): ValidObject?
 
     /**
      * String to identify the transaction.
diff --git a/matrix-sdk-android/src/main/java/im/vector/matrix/android/internal/crypto/verification/VerificationInfoAccept.kt b/matrix-sdk-android/src/main/java/im/vector/matrix/android/internal/crypto/verification/VerificationInfoAccept.kt
index cc6c8c8530c..7adb94374a8 100644
--- a/matrix-sdk-android/src/main/java/im/vector/matrix/android/internal/crypto/verification/VerificationInfoAccept.kt
+++ b/matrix-sdk-android/src/main/java/im/vector/matrix/android/internal/crypto/verification/VerificationInfoAccept.kt
@@ -15,7 +15,9 @@
  */
 package im.vector.matrix.android.internal.crypto.verification
 
-internal interface VerificationInfoAccept : VerificationInfo {
+import timber.log.Timber
+
+internal interface VerificationInfoAccept : VerificationInfo<ValidVerificationInfoAccept> {
     /**
      * The key agreement protocol that Bob’s device has selected to use, out of the list proposed by Alice’s device
      */
@@ -41,6 +43,27 @@ internal interface VerificationInfoAccept : VerificationInfo {
      *  and the canonical JSON representation of the m.key.verification.start message.
      */
     var commitment: String?
+
+    override fun asValidObject(): ValidVerificationInfoAccept? {
+        if (transactionID.isNullOrBlank()
+                || keyAgreementProtocol.isNullOrBlank()
+                || hash.isNullOrBlank()
+                || commitment.isNullOrBlank()
+                || messageAuthenticationCode.isNullOrBlank()
+                || shortAuthenticationStrings.isNullOrEmpty()) {
+            Timber.e("## received invalid verification request")
+            return null
+        }
+
+        return ValidVerificationInfoAccept(
+                transactionID!!,
+                keyAgreementProtocol!!,
+                hash!!,
+                messageAuthenticationCode!!,
+                shortAuthenticationStrings!!,
+                commitment
+        )
+    }
 }
 
 internal interface VerificationInfoAcceptFactory {
@@ -52,3 +75,12 @@ internal interface VerificationInfoAcceptFactory {
                messageAuthenticationCode: String,
                shortAuthenticationStrings: List<String>): VerificationInfoAccept
 }
+
+internal data class ValidVerificationInfoAccept(
+        val transactionID: String,
+        val keyAgreementProtocol: String,
+        val hash: String,
+        val messageAuthenticationCode: String,
+        val shortAuthenticationStrings: List<String>,
+        var commitment: String?
+)
diff --git a/matrix-sdk-android/src/main/java/im/vector/matrix/android/internal/crypto/verification/VerificationInfoCancel.kt b/matrix-sdk-android/src/main/java/im/vector/matrix/android/internal/crypto/verification/VerificationInfoCancel.kt
index 713453e93e8..4de77993e03 100644
--- a/matrix-sdk-android/src/main/java/im/vector/matrix/android/internal/crypto/verification/VerificationInfoCancel.kt
+++ b/matrix-sdk-android/src/main/java/im/vector/matrix/android/internal/crypto/verification/VerificationInfoCancel.kt
@@ -15,7 +15,7 @@
  */
 package im.vector.matrix.android.internal.crypto.verification
 
-internal interface VerificationInfoCancel : VerificationInfo {
+internal interface VerificationInfoCancel : VerificationInfo<ValidVerificationInfoCancel> {
     /**
      * machine-readable reason for cancelling, see [CancelCode]
      */
@@ -25,4 +25,19 @@ internal interface VerificationInfoCancel : VerificationInfo {
      * human-readable reason for cancelling.  This should only be used if the receiving client does not understand the code given.
      */
     val reason: String?
+
+    override fun asValidObject(): ValidVerificationInfoCancel? {
+        if (transactionID.isNullOrBlank() || code.isNullOrBlank()) {
+            return null
+        }
+        return ValidVerificationInfoCancel(
+                code!!,
+                reason
+        )
+    }
 }
+
+internal data class ValidVerificationInfoCancel(
+        val code: String,
+        val reason: String?
+)
diff --git a/matrix-sdk-android/src/main/java/im/vector/matrix/android/internal/crypto/verification/VerificationInfoDone.kt b/matrix-sdk-android/src/main/java/im/vector/matrix/android/internal/crypto/verification/VerificationInfoDone.kt
index 9c7c00e84b6..e0af4318a1a 100644
--- a/matrix-sdk-android/src/main/java/im/vector/matrix/android/internal/crypto/verification/VerificationInfoDone.kt
+++ b/matrix-sdk-android/src/main/java/im/vector/matrix/android/internal/crypto/verification/VerificationInfoDone.kt
@@ -15,4 +15,14 @@
  */
 package im.vector.matrix.android.internal.crypto.verification
 
-interface VerificationInfoDone : VerificationInfo
+internal interface VerificationInfoDone : VerificationInfo<ValidVerificationInfoDone> {
+
+    override fun asValidObject(): ValidVerificationInfoDone? {
+        if (transactionID.isNullOrBlank()) {
+            return null
+        }
+        return ValidVerificationInfoDone
+    }
+}
+
+internal object ValidVerificationInfoDone
diff --git a/matrix-sdk-android/src/main/java/im/vector/matrix/android/internal/crypto/verification/VerificationInfoKey.kt b/matrix-sdk-android/src/main/java/im/vector/matrix/android/internal/crypto/verification/VerificationInfoKey.kt
index 2466660ca4b..15b3703c592 100644
--- a/matrix-sdk-android/src/main/java/im/vector/matrix/android/internal/crypto/verification/VerificationInfoKey.kt
+++ b/matrix-sdk-android/src/main/java/im/vector/matrix/android/internal/crypto/verification/VerificationInfoKey.kt
@@ -18,13 +18,26 @@ package im.vector.matrix.android.internal.crypto.verification
 /**
  * Sent by both devices to send their ephemeral Curve25519 public key to the other device.
  */
-internal interface VerificationInfoKey : VerificationInfo {
+internal interface VerificationInfoKey : VerificationInfo<ValidVerificationInfoKey> {
     /**
      * The device’s ephemeral public key, as an unpadded base64 string
      */
     val key: String?
+
+    override fun asValidObject(): ValidVerificationInfoKey? {
+        if (transactionID.isNullOrBlank() || key.isNullOrBlank()) {
+            return null
+        }
+        return ValidVerificationInfoKey(
+                key!!
+        )
+    }
 }
 
 internal interface VerificationInfoKeyFactory {
     fun create(tid: String, pubKey: String): VerificationInfoKey
 }
+
+internal data class ValidVerificationInfoKey(
+        val key: String
+)
diff --git a/matrix-sdk-android/src/main/java/im/vector/matrix/android/internal/crypto/verification/VerificationInfoMac.kt b/matrix-sdk-android/src/main/java/im/vector/matrix/android/internal/crypto/verification/VerificationInfoMac.kt
index e895973ae86..68c86249d48 100644
--- a/matrix-sdk-android/src/main/java/im/vector/matrix/android/internal/crypto/verification/VerificationInfoMac.kt
+++ b/matrix-sdk-android/src/main/java/im/vector/matrix/android/internal/crypto/verification/VerificationInfoMac.kt
@@ -15,7 +15,7 @@
  */
 package im.vector.matrix.android.internal.crypto.verification
 
-internal interface VerificationInfoMac : VerificationInfo {
+internal interface VerificationInfoMac : VerificationInfo<ValidVerificationInfoMac> {
     /**
      * A map of key ID to the MAC of the key, as an unpadded base64 string, calculated using the MAC key
      */
@@ -28,8 +28,23 @@ internal interface VerificationInfoMac : VerificationInfo {
      *  give the MAC of the string “ed25519:ABCDEFG,ed25519:HIJKLMN”.
      */
     val keys: String?
+
+    override fun asValidObject(): ValidVerificationInfoMac? {
+        if (transactionID.isNullOrBlank() || keys.isNullOrBlank() || mac.isNullOrEmpty()) {
+            return null
+        }
+        return ValidVerificationInfoMac(
+                mac!!,
+                keys!!
+        )
+    }
 }
 
 internal interface VerificationInfoMacFactory {
-    fun create(tid: String, mac: Map<String, String>, keys: String) : VerificationInfoMac
+    fun create(tid: String, mac: Map<String, String>, keys: String): VerificationInfoMac
 }
+
+internal data class ValidVerificationInfoMac(
+        val mac: Map<String, String>,
+        val keys: String
+)
diff --git a/matrix-sdk-android/src/main/java/im/vector/matrix/android/internal/crypto/verification/VerificationInfoReady.kt b/matrix-sdk-android/src/main/java/im/vector/matrix/android/internal/crypto/verification/VerificationInfoReady.kt
index 4c269513159..aa998b2258e 100644
--- a/matrix-sdk-android/src/main/java/im/vector/matrix/android/internal/crypto/verification/VerificationInfoReady.kt
+++ b/matrix-sdk-android/src/main/java/im/vector/matrix/android/internal/crypto/verification/VerificationInfoReady.kt
@@ -23,7 +23,7 @@ package im.vector.matrix.android.internal.crypto.verification
  * with a m.key.verification.start event instead.
  */
 
-interface VerificationInfoReady : VerificationInfo {
+internal interface VerificationInfoReady : VerificationInfo<ValidVerificationInfoReady> {
     /**
      * The ID of the device that sent the m.key.verification.ready message
      */
@@ -33,8 +33,26 @@ interface VerificationInfoReady : VerificationInfo {
      * An array of verification methods that the device supports
      */
     val methods: List<String>?
+
+    override fun asValidObject(): ValidVerificationInfoReady? {
+        if (transactionID.isNullOrBlank()
+                || fromDevice.isNullOrBlank()
+                || methods.isNullOrEmpty()) {
+            return null
+        }
+
+        return ValidVerificationInfoReady(
+                fromDevice!!,
+                methods!!
+        )
+    }
 }
 
 internal interface MessageVerificationReadyFactory {
     fun create(tid: String, methods: List<String>, fromDevice: String): VerificationInfoReady
 }
+
+internal data class ValidVerificationInfoReady(
+        val fromDevice: String,
+        val methods: List<String>
+)
diff --git a/matrix-sdk-android/src/main/java/im/vector/matrix/android/internal/crypto/verification/VerificationInfoRequest.kt b/matrix-sdk-android/src/main/java/im/vector/matrix/android/internal/crypto/verification/VerificationInfoRequest.kt
index 529334c3ea5..a4a12336699 100644
--- a/matrix-sdk-android/src/main/java/im/vector/matrix/android/internal/crypto/verification/VerificationInfoRequest.kt
+++ b/matrix-sdk-android/src/main/java/im/vector/matrix/android/internal/crypto/verification/VerificationInfoRequest.kt
@@ -15,7 +15,7 @@
  */
 package im.vector.matrix.android.internal.crypto.verification
 
-interface VerificationInfoRequest : VerificationInfo {
+internal interface VerificationInfoRequest : VerificationInfo<ValidVerificationInfoRequest> {
 
     /**
      * Required. The device ID which is initiating the request.
@@ -33,4 +33,22 @@ interface VerificationInfoRequest : VerificationInfo {
      * the message should be ignored by the receiver.
      */
     val timestamp: Long?
+
+    override fun asValidObject(): ValidVerificationInfoRequest? {
+        // FIXME No check on Timestamp?
+        if (transactionID.isNullOrBlank() || methods.isNullOrEmpty() || fromDevice.isNullOrEmpty()) {
+            return null
+        }
+        return ValidVerificationInfoRequest(
+                fromDevice!!,
+                methods!!,
+                timestamp
+        )
+    }
 }
+
+internal data class ValidVerificationInfoRequest(
+        val fromDevice: String,
+        val methods: List<String>,
+        val timestamp: Long?
+)
diff --git a/matrix-sdk-android/src/main/java/im/vector/matrix/android/internal/crypto/verification/VerificationInfoStart.kt b/matrix-sdk-android/src/main/java/im/vector/matrix/android/internal/crypto/verification/VerificationInfoStart.kt
index bd4fd529803..985e7c05f6d 100644
--- a/matrix-sdk-android/src/main/java/im/vector/matrix/android/internal/crypto/verification/VerificationInfoStart.kt
+++ b/matrix-sdk-android/src/main/java/im/vector/matrix/android/internal/crypto/verification/VerificationInfoStart.kt
@@ -18,9 +18,8 @@ package im.vector.matrix.android.internal.crypto.verification
 import im.vector.matrix.android.api.session.crypto.verification.SasMode
 import im.vector.matrix.android.internal.crypto.model.rest.VERIFICATION_METHOD_RECIPROCATE
 import im.vector.matrix.android.internal.crypto.model.rest.VERIFICATION_METHOD_SAS
-import timber.log.Timber
 
-internal interface VerificationInfoStart : VerificationInfo {
+internal interface VerificationInfoStart : VerificationInfo<ValidVerificationInfoStart> {
 
     val method: String?
 
@@ -64,40 +63,54 @@ internal interface VerificationInfoStart : VerificationInfo {
 
     fun toCanonicalJson(): String?
 
-    override fun isValid(): Boolean {
+    override fun asValidObject(): ValidVerificationInfoStart? {
         if (transactionID.isNullOrBlank()
-                || fromDevice.isNullOrBlank()
-                || (method == VERIFICATION_METHOD_SAS && !isValidSas())
-                || (method == VERIFICATION_METHOD_RECIPROCATE && !isValidReciprocate())) {
-            Timber.e("## received invalid verification request")
-            return false
+                || fromDevice.isNullOrBlank()) {
+            return null
         }
-        return true
-    }
-
-    private fun isValidSas(): Boolean {
-        val myHashes = hashes
-        val myMessageAuthenticationCodes = messageAuthenticationCodes
-        val myShortAuthenticationStrings = shortAuthenticationStrings
 
-        if (keyAgreementProtocols.isNullOrEmpty()
-                || myHashes.isNullOrEmpty()
-                || !myHashes.contains("sha256") || myMessageAuthenticationCodes.isNullOrEmpty()
-                || (!myMessageAuthenticationCodes.contains(SASDefaultVerificationTransaction.SAS_MAC_SHA256)
-                        && !myMessageAuthenticationCodes.contains(SASDefaultVerificationTransaction.SAS_MAC_SHA256_LONGKDF))
-                || myShortAuthenticationStrings.isNullOrEmpty()
-                || !myShortAuthenticationStrings.contains(SasMode.DECIMAL)) {
-            return false
+        return when (method) {
+            VERIFICATION_METHOD_SAS         -> {
+                if (keyAgreementProtocols.isNullOrEmpty()
+                        || hashes.isNullOrEmpty()
+                        || !hashes!!.contains("sha256") || messageAuthenticationCodes.isNullOrEmpty()
+                        || (!messageAuthenticationCodes!!.contains(SASDefaultVerificationTransaction.SAS_MAC_SHA256)
+                                && !messageAuthenticationCodes!!.contains(SASDefaultVerificationTransaction.SAS_MAC_SHA256_LONGKDF))
+                        || shortAuthenticationStrings.isNullOrEmpty()
+                        || !shortAuthenticationStrings!!.contains(SasMode.DECIMAL)) {
+                    null
+                } else {
+                    ValidVerificationInfoStart.SasVerificationInfoStart(
+                            keyAgreementProtocols!!,
+                            hashes!!,
+                            messageAuthenticationCodes!!,
+                            shortAuthenticationStrings!!
+                    )
+                }
+            }
+            VERIFICATION_METHOD_RECIPROCATE -> {
+                if (sharedSecret.isNullOrBlank()) {
+                    null
+                } else {
+                    ValidVerificationInfoStart.ReciprocateVerificationInfoStart(
+                            sharedSecret!!
+                    )
+                }
+            }
+            else                            -> null
         }
-
-        return true
     }
+}
 
-    private fun isValidReciprocate(): Boolean {
-        if (sharedSecret.isNullOrBlank()) {
-            return false
-        }
-
-        return true
-    }
+sealed class ValidVerificationInfoStart {
+    data class SasVerificationInfoStart(
+            val keyAgreementProtocols: List<String>,
+            val hashes: List<String>,
+            val messageAuthenticationCodes: List<String>,
+            val shortAuthenticationStrings: List<String>
+    ) : ValidVerificationInfoStart()
+
+    data class ReciprocateVerificationInfoStart(
+            val sharedSecret: String
+    ) : ValidVerificationInfoStart()
 }