diff --git a/node/src/main/kotlin/net/corda/node/internal/cordapp/JarScanningCordappLoader.kt b/node/src/main/kotlin/net/corda/node/internal/cordapp/JarScanningCordappLoader.kt
index 958f18baf1..6bcdf1d577 100644
--- a/node/src/main/kotlin/net/corda/node/internal/cordapp/JarScanningCordappLoader.kt
+++ b/node/src/main/kotlin/net/corda/node/internal/cordapp/JarScanningCordappLoader.kt
@@ -209,10 +209,20 @@ class JarScanningCordappLoader(private val cordappJars: Set<Path>,
                                 "(${newerCordapp.contractVersionId}) than corresponding legacy contract CorDapp " +
                                 "'${legacyCordapp.jarFile}' (${legacyCordapp.contractVersionId})"
                     }
+                    checkSignersMatch(legacyCordapp, newerCordapp)
                 }
             }
         }
 
+        private fun checkSignersMatch(legacyCordapp: CordappImpl, nonLegacyCordapp: CordappImpl) {
+            val legacySigners = legacyCordapp.jarPath.openStream().let(::JarInputStream).use(JarSignatureCollector::collectSigners)
+            val nonLegacySigners = nonLegacyCordapp.jarPath.openStream().let(::JarInputStream).use(JarSignatureCollector::collectSigners)
+            check(legacySigners == nonLegacySigners) {
+                "Newer contract CorDapp '${nonLegacyCordapp.jarFile}' signers do not match legacy contract CorDapp " +
+                        "'${legacyCordapp.jarFile}' signers."
+            }
+        }
+
         private val CordappImpl.contractVersionId: Int
             get() = when (val info = info) {
                 is Cordapp.Info.Contract -> info.versionId
diff --git a/node/src/test/kotlin/net/corda/node/internal/cordapp/JarScanningCordappLoaderTest.kt b/node/src/test/kotlin/net/corda/node/internal/cordapp/JarScanningCordappLoaderTest.kt
index 4de05a3910..956f2bd3fd 100644
--- a/node/src/test/kotlin/net/corda/node/internal/cordapp/JarScanningCordappLoaderTest.kt
+++ b/node/src/test/kotlin/net/corda/node/internal/cordapp/JarScanningCordappLoaderTest.kt
@@ -264,6 +264,33 @@ class JarScanningCordappLoaderTest {
         assertThat(loader.legacyContractCordapps.single().jarFile).isEqualTo(legacyFinanceContractsJar)
     }
 
+    @Test(timeout=300_000)
+    fun `exception raised if legacy and non legacy version of same contract signed by differet keys`() {
+        val jar = currentFinanceContractsJar.duplicate {
+            tempFolder.root.toPath().generateKey("testAlias", "testPassword", ALICE_NAME.toString())
+            tempFolder.root.toPath().signJar(absolutePathString(), "testAlias", "testPassword")
+        }
+        assertThatIllegalStateException()
+                .isThrownBy { JarScanningCordappLoader(setOf(jar), setOf(legacyFinanceContractsJar)).cordapps }
+                .withMessageContaining("signers do not match legacy contract CorDapp")
+    }
+
+    @Test(timeout=300_000)
+    fun `loads legacy and non legacy version of same contract both signed by 2 keys`() {
+        val jar = currentFinanceContractsJar.duplicate {
+            tempFolder.root.toPath().generateKey("testAlias", "testPassword", ALICE_NAME.toString())
+            tempFolder.root.toPath().signJar(absolutePathString(), "testAlias", "testPassword")
+        }
+        val legacyJar = legacyFinanceContractsJar.duplicate(name = "duplicate2.jar") {
+            tempFolder.root.toPath().signJar(absolutePathString(), "testAlias", "testPassword")
+        }
+        val loader = JarScanningCordappLoader(setOf(jar), setOf(legacyJar))
+        assertThat(jar.parent.getJarSigners(jar.name)).hasSize(2)
+        assertThat(legacyJar.parent.getJarSigners(legacyJar.name)).hasSize(2)
+        assertThat(loader.cordapps).hasSize(1)
+        assertThat(loader.legacyContractCordapps).hasSize(1)
+    }
+
     @Test(timeout=300_000)
     fun `does not load legacy contracts CorDapp without the corresponding current version`() {
         val loader = JarScanningCordappLoader(setOf(currentFinanceWorkflowsJar), setOf(legacyFinanceContractsJar))