diff --git a/modules/openid-federation-client/src/jvmTest/kotlin/com/sphereon/oid/fed/client/validation/MockJwtService.kt b/modules/openid-federation-client/src/jvmTest/kotlin/com/sphereon/oid/fed/client/validation/MockJwtService.kt
new file mode 100644
index 00000000..4aac5382
--- /dev/null
+++ b/modules/openid-federation-client/src/jvmTest/kotlin/com/sphereon/oid/fed/client/validation/MockJwtService.kt
@@ -0,0 +1,57 @@
+package com.sphereon.oid.fed.client.validation
+
+import com.nimbusds.jose.JOSEObjectType
+import com.nimbusds.jose.JWSAlgorithm
+import com.nimbusds.jose.JWSHeader
+import com.nimbusds.jose.JWSSigner
+import com.nimbusds.jose.JWSVerifier
+import com.nimbusds.jose.crypto.ECDSASigner
+import com.nimbusds.jose.crypto.ECDSAVerifier
+import com.nimbusds.jose.jwk.ECKey
+import com.nimbusds.jwt.JWTClaimsSet
+import com.nimbusds.jwt.SignedJWT
+import com.sphereon.oid.fed.common.jwt.IJwtService
+import com.sphereon.oid.fed.common.jwt.JwtSignInput
+import com.sphereon.oid.fed.common.jwt.JwtVerifyInput
+import com.sphereon.oid.fed.openapi.models.JWTHeader
+import kotlinx.serialization.encodeToString
+import kotlinx.serialization.json.Json
+import kotlinx.serialization.json.JsonObject
+
+class MockJwtService : IJwtService {
+
+    override suspend fun sign(input: JwtSignInput): String {
+        val jwkJsonString = Json.encodeToString(input.key)
+        val ecJWK = ECKey.parse(jwkJsonString)
+        val signer: JWSSigner = ECDSASigner(ecJWK)
+        val jwsHeader = input.header.toJWSHeader()
+
+        val signedJWT = SignedJWT(
+            jwsHeader, JWTClaimsSet.parse(JsonObject(input.payload).toString())
+        )
+
+        signedJWT.sign(signer)
+        return signedJWT.serialize()
+    }
+
+    override suspend fun verify(input: JwtVerifyInput): Boolean {
+        try {
+            val jwkJsonString = Json.encodeToString(input.key)
+            val ecKey = ECKey.parse(jwkJsonString)
+            val verifier: JWSVerifier = ECDSAVerifier(ecKey)
+            val signedJWT = SignedJWT.parse(input.jwt)
+            val verified = signedJWT.verify(verifier)
+            return verified
+        } catch (e: Exception) {
+            throw Exception("Couldn't verify the JWT Signature: ${e.message}", e)
+        }
+    }
+
+    private fun JWTHeader.toJWSHeader(): JWSHeader {
+        val type = typ
+        return JWSHeader.Builder(JWSAlgorithm.parse(alg)).apply {
+            type(JOSEObjectType(type))
+            keyID(kid)
+        }.build()
+    }
+}
diff --git a/modules/openid-federation-client/src/jvmTest/kotlin/com/sphereon/oid/fed/client/validation/TrustChainValidationTest.kt b/modules/openid-federation-client/src/jvmTest/kotlin/com/sphereon/oid/fed/client/validation/TrustChainValidationTest.kt
index 3a486ad0..a202a9c6 100644
--- a/modules/openid-federation-client/src/jvmTest/kotlin/com/sphereon/oid/fed/client/validation/TrustChainValidationTest.kt
+++ b/modules/openid-federation-client/src/jvmTest/kotlin/com/sphereon/oid/fed/client/validation/TrustChainValidationTest.kt
@@ -1,21 +1,9 @@
 package com.sphereon.oid.fed.client.validation
 
-import com.nimbusds.jose.JOSEObjectType
-import com.nimbusds.jose.JWSAlgorithm
-import com.nimbusds.jose.JWSHeader
-import com.nimbusds.jose.JWSSigner
-import com.nimbusds.jose.JWSVerifier
-import com.nimbusds.jose.crypto.ECDSASigner
-import com.nimbusds.jose.crypto.ECDSAVerifier
 import com.nimbusds.jose.jwk.Curve
 import com.nimbusds.jose.jwk.ECKey
 import com.nimbusds.jose.jwk.gen.ECKeyGenerator
-import com.nimbusds.jwt.JWTClaimsSet
-import com.nimbusds.jwt.SignedJWT
-import com.sphereon.oid.fed.client.OidFederationClientService.TRUST_CHAIN_VALIDATION
-import com.sphereon.oid.fed.common.jwt.IJwtService
 import com.sphereon.oid.fed.common.jwt.JwtSignInput
-import com.sphereon.oid.fed.common.jwt.JwtVerifyInput
 import com.sphereon.oid.fed.openapi.models.*
 import io.ktor.client.engine.mock.*
 import io.ktor.client.engine.mock.MockEngine.Companion.invoke
@@ -23,7 +11,6 @@ import io.ktor.http.*
 import junit.framework.TestCase.assertTrue
 import kotlinx.coroutines.runBlocking
 import kotlinx.coroutines.test.runTest
-import kotlinx.serialization.encodeToString
 import kotlinx.serialization.json.Json
 import kotlinx.serialization.json.JsonArray
 import kotlinx.serialization.json.JsonObject
@@ -34,48 +21,11 @@ import java.time.OffsetDateTime
 import kotlin.test.Test
 import kotlin.test.assertEquals
 
-class JwtServiceImpl : IJwtService {
-    override suspend fun sign(input: JwtSignInput): String {
-        val jwkJsonString = Json.encodeToString(input.key)
-        val ecJWK = ECKey.parse(jwkJsonString)
-        val signer: JWSSigner = ECDSASigner(ecJWK)
-        val jwsHeader = input.header.toJWSHeader()
-
-        val signedJWT = SignedJWT(
-            jwsHeader, JWTClaimsSet.parse(JsonObject(input.payload).toString())
-        )
-
-        signedJWT.sign(signer)
-        return signedJWT.serialize()
-    }
-
-    override suspend fun verify(input: JwtVerifyInput): Boolean {
-        try {
-            val jwkJsonString = Json.encodeToString(input.key)
-            val ecKey = ECKey.parse(jwkJsonString)
-            val verifier: JWSVerifier = ECDSAVerifier(ecKey)
-            val signedJWT = SignedJWT.parse(input.jwt)
-            val verified = signedJWT.verify(verifier)
-            return verified
-        } catch (e: Exception) {
-            throw Exception("Couldn't verify the JWT Signature: ${e.message}", e)
-        }
-    }
-
-    private fun JWTHeader.toJWSHeader(): JWSHeader {
-        val type = typ
-        return JWSHeader.Builder(JWSAlgorithm.parse(alg)).apply {
-            type(JOSEObjectType(type))
-            keyID(kid)
-        }.build()
-    }
-}
-
 class TrustChainValidationTest {
 
     companion object {
 
-        val jwtService = JwtServiceImpl()
+        val jwtService = MockJwtService()
 
         // key pairs
         val partyBKeyPair = ECKeyGenerator(Curve.P_256).generate()