diff --git a/bundles/org.eclipse.equinox.p2.artifact.repository/src/org/eclipse/equinox/internal/p2/artifact/processors/pgp/Messages.java b/bundles/org.eclipse.equinox.p2.artifact.repository/src/org/eclipse/equinox/internal/p2/artifact/processors/pgp/Messages.java
index f02a440..4f522f0 100644
--- a/bundles/org.eclipse.equinox.p2.artifact.repository/src/org/eclipse/equinox/internal/p2/artifact/processors/pgp/Messages.java
+++ b/bundles/org.eclipse.equinox.p2.artifact.repository/src/org/eclipse/equinox/internal/p2/artifact/processors/pgp/Messages.java
@@ -23,7 +23,7 @@
 
 	public static String Error_CouldNotLoadSignature;
 
-	public static String Error_publicKeyNotFound;
+	public static String Warning_publicKeyNotFound;
 
 	static {
 		// initialize resource bundle
diff --git a/bundles/org.eclipse.equinox.p2.artifact.repository/src/org/eclipse/equinox/internal/p2/artifact/processors/pgp/PGPSignatureVerifier.java b/bundles/org.eclipse.equinox.p2.artifact.repository/src/org/eclipse/equinox/internal/p2/artifact/processors/pgp/PGPSignatureVerifier.java
index d6267b6..b994b77 100644
--- a/bundles/org.eclipse.equinox.p2.artifact.repository/src/org/eclipse/equinox/internal/p2/artifact/processors/pgp/PGPSignatureVerifier.java
+++ b/bundles/org.eclipse.equinox.p2.artifact.repository/src/org/eclipse/equinox/internal/p2/artifact/processors/pgp/PGPSignatureVerifier.java
@@ -137,25 +137,25 @@
 			long keyID = signature.getKeyID();
 			Collection<PGPPublicKey> keys = keyService.getKeys(keyID);
 			if (keys.isEmpty()) {
-				setStatus(new Status(IStatus.ERROR, Activator.ID,
-						NLS.bind(Messages.Error_publicKeyNotFound, PGPPublicKeyService.toHex(keyID))));
-				return;
-			}
-
-			try {
-				PGPContentVerifierBuilder verifierBuilder = new BcPGPContentVerifierBuilderProvider()
-						.get(signature.getKeyAlgorithm(), signature.getHashAlgorithm());
-				List<PGPContentVerifier> verifiers = new ArrayList<>();
-				signaturesToVerify.put(signature, verifiers);
-				for (PGPPublicKey key : keys) {
-					PGPContentVerifier verifier = verifierBuilder.build(key);
-					verifierKeys.put(verifier, key);
-					verifiers.add(verifier);
-					signatureVerifiers.add(verifier.getOutputStream());
+				LogHelper.log(new Status(IStatus.WARNING, Activator.ID,
+						NLS.bind(Messages.Warning_publicKeyNotFound, PGPPublicKeyService.toHex(keyID),
+								context.getArtifactKey().getId())));
+			} else {
+				try {
+					PGPContentVerifierBuilder verifierBuilder = new BcPGPContentVerifierBuilderProvider()
+							.get(signature.getKeyAlgorithm(), signature.getHashAlgorithm());
+					List<PGPContentVerifier> verifiers = new ArrayList<>();
+					signaturesToVerify.put(signature, verifiers);
+					for (PGPPublicKey key : keys) {
+						PGPContentVerifier verifier = verifierBuilder.build(key);
+						verifierKeys.put(verifier, key);
+						verifiers.add(verifier);
+						signatureVerifiers.add(verifier.getOutputStream());
+					}
+				} catch (PGPException ex) {
+					setStatus(new Status(IStatus.ERROR, Activator.ID, ex.getMessage(), ex));
+					return;
 				}
-			} catch (PGPException ex) {
-				setStatus(new Status(IStatus.ERROR, Activator.ID, ex.getMessage(), ex));
-				return;
 			}
 		}
 	}
diff --git a/bundles/org.eclipse.equinox.p2.artifact.repository/src/org/eclipse/equinox/internal/p2/artifact/processors/pgp/messages.properties b/bundles/org.eclipse.equinox.p2.artifact.repository/src/org/eclipse/equinox/internal/p2/artifact/processors/pgp/messages.properties
index 1d12500..09a1e72 100644
--- a/bundles/org.eclipse.equinox.p2.artifact.repository/src/org/eclipse/equinox/internal/p2/artifact/processors/pgp/messages.properties
+++ b/bundles/org.eclipse.equinox.p2.artifact.repository/src/org/eclipse/equinox/internal/p2/artifact/processors/pgp/messages.properties
@@ -13,4 +13,4 @@
 Error_SignatureAfterKeyExpiration=The signature is created after the expiration time of the signature's key {0}
 Error_SignatureAndFileDontMatch=The signature is invalid for current content
 Error_CouldNotLoadSignature=The signatures could not be loaded
-Error_publicKeyNotFound=A public key with ID {0} needed to verify the signatures could not be found
+Warning_publicKeyNotFound=A public key with ID {0} needed to verify the signatures of {1} could not be found
diff --git a/bundles/org.eclipse.equinox.p2.tests/src/org/eclipse/equinox/p2/tests/artifact/processors/PGPSignatureVerifierTest.java b/bundles/org.eclipse.equinox.p2.tests/src/org/eclipse/equinox/p2/tests/artifact/processors/PGPSignatureVerifierTest.java
index 2dd294f..dd33567 100644
--- a/bundles/org.eclipse.equinox.p2.tests/src/org/eclipse/equinox/p2/tests/artifact/processors/PGPSignatureVerifierTest.java
+++ b/bundles/org.eclipse.equinox.p2.tests/src/org/eclipse/equinox/p2/tests/artifact/processors/PGPSignatureVerifierTest.java
@@ -13,6 +13,7 @@
 import static org.junit.Assert.assertEquals;
 import static org.junit.Assert.assertTrue;
 
+import java.io.ByteArrayOutputStream;
 import java.io.File;
 import java.io.IOException;
 import java.io.InputStream;
@@ -20,7 +21,9 @@
 import java.nio.file.Files;
 import java.util.Set;
 import org.eclipse.core.runtime.FileLocator;
+import org.eclipse.core.runtime.IAdaptable;
 import org.eclipse.core.runtime.IStatus;
+import org.eclipse.core.runtime.NullProgressMonitor;
 import org.eclipse.equinox.internal.p2.artifact.processors.pgp.PGPSignatureVerifier;
 import org.eclipse.equinox.internal.p2.metadata.ArtifactKey;
 import org.eclipse.equinox.internal.provisional.p2.repository.DefaultPGPPublicKeyService;
@@ -73,6 +76,23 @@
 		return res;
 	}
 
+	private static class ArtifactOutputStream extends ByteArrayOutputStream implements IAdaptable {
+		IArtifactDescriptor descriptor = new ArtifactDescriptor(
+				new ArtifactKey("whatever", "whatever", Version.parseVersion("1.0.0")));
+
+		public IArtifactDescriptor getDescriptor() {
+			return descriptor;
+		}
+
+		@Override
+		public <T> T getAdapter(Class<T> adapter) {
+			if (adapter.isInstance(descriptor)) {
+				return adapter.cast(descriptor);
+			}
+			return null;
+		}
+	}
+
 	private String read(String resource) throws IOException, URISyntaxException {
 		return Files.readString(new File(FileLocator.toFileURL(getClass().getResource(resource)).toURI()).toPath());
 	}
@@ -84,6 +104,8 @@
 		@SuppressWarnings("resource")
 		PGPSignatureVerifier verifier = new PGPSignatureVerifier();
 		verifier.initialize(agentProvider.getAgent(), processingStepDescriptor, artifact);
+		ArtifactOutputStream artifactOutputStream = new ArtifactOutputStream();
+		verifier.link(artifactOutputStream, new NullProgressMonitor());
 		Assert.assertTrue(verifier.getStatus().toString(), verifier.getStatus().isOK());
 		try (InputStream bytes = getClass().getResourceAsStream("testArtifact")) {
 			bytes.transferTo(verifier);
@@ -91,6 +113,12 @@
 		Assert.assertTrue(verifier.getStatus().isOK());
 		verifier.close();
 		Assert.assertTrue(verifier.getStatus().isOK());
+
+		IArtifactDescriptor descriptor = artifactOutputStream.getDescriptor();
+		Assert.assertNotNull("Signatures should be present",
+				descriptor.getProperty(PGPSignatureVerifier.PGP_SIGNATURES_PROPERTY_NAME));
+		Assert.assertNotNull("Keys should be present",
+				descriptor.getProperty(PGPSignatureVerifier.PGP_SIGNER_KEYS_PROPERTY_NAME));
 	}
 
 	@Test
@@ -99,9 +127,21 @@
 		IArtifactDescriptor artifact = createArtifact("signed_by_signer_1", "public_signer2.pgp");
 		try (PGPSignatureVerifier verifier = new PGPSignatureVerifier()) {
 			verifier.initialize(agentProvider.getAgent(), processingStepDescriptor, artifact);
-			IStatus status = verifier.getStatus();
-			assertEquals(IStatus.ERROR, status.getSeverity());
-			assertTrue(status.getMessage().matches("A public key.*could not be found.*"));
+			ArtifactOutputStream artifactOutputStream = new ArtifactOutputStream();
+			verifier.link(artifactOutputStream, new NullProgressMonitor());
+			Assert.assertTrue(verifier.getStatus().toString(), verifier.getStatus().isOK());
+			try (InputStream bytes = getClass().getResourceAsStream("testArtifact")) {
+				bytes.transferTo(verifier);
+			}
+			Assert.assertTrue(verifier.getStatus().isOK());
+			verifier.close();
+			Assert.assertTrue(verifier.getStatus().isOK());
+
+			IArtifactDescriptor descriptor = artifactOutputStream.getDescriptor();
+			Assert.assertNull("No signatures should be present",
+					descriptor.getProperty(PGPSignatureVerifier.PGP_SIGNATURES_PROPERTY_NAME));
+			Assert.assertNull("No keys should be present",
+					descriptor.getProperty(PGPSignatureVerifier.PGP_SIGNER_KEYS_PROPERTY_NAME));
 		}
 	}
 
diff --git a/bundles/org.eclipse.equinox.p2.tests/src/org/eclipse/equinox/p2/tests/artifact/repository/PGPVerifierTest.java b/bundles/org.eclipse.equinox.p2.tests/src/org/eclipse/equinox/p2/tests/artifact/repository/PGPVerifierTest.java
index fe9d5fc..0d4525b 100644
--- a/bundles/org.eclipse.equinox.p2.tests/src/org/eclipse/equinox/p2/tests/artifact/repository/PGPVerifierTest.java
+++ b/bundles/org.eclipse.equinox.p2.tests/src/org/eclipse/equinox/p2/tests/artifact/repository/PGPVerifierTest.java
@@ -19,14 +19,17 @@
 import java.util.stream.Stream;
 import org.eclipse.core.runtime.IStatus;
 import org.eclipse.core.runtime.NullProgressMonitor;
+import org.eclipse.equinox.internal.p2.artifact.processors.pgp.PGPSignatureVerifier;
 import org.eclipse.equinox.internal.p2.artifact.repository.MirrorRequest;
 import org.eclipse.equinox.internal.p2.metadata.ArtifactKey;
 import org.eclipse.equinox.internal.provisional.p2.repository.DefaultPGPPublicKeyService;
 import org.eclipse.equinox.p2.core.IAgentLocation;
 import org.eclipse.equinox.p2.metadata.Version;
+import org.eclipse.equinox.p2.repository.artifact.IArtifactDescriptor;
 import org.eclipse.equinox.p2.repository.artifact.IArtifactRepository;
 import org.eclipse.equinox.p2.repository.spi.PGPPublicKeyService;
 import org.eclipse.equinox.p2.tests.AbstractProvisioningTest;
+import org.junit.Assert;
 import org.junit.Before;
 import org.junit.Test;
 
@@ -49,17 +52,35 @@
 
 	@Test
 	public void testAllGood() throws Exception {
-		IStatus mirrorStatus = performMirrorFrom("repoPGPOK");
+		MirrorRequest mirrorRequest = performMirrorFrom("repoPGPOK");
+		IStatus mirrorStatus = mirrorRequest.getResult();
 		assertOK(mirrorStatus);
+
+		IArtifactDescriptor[] artifactDescriptors = targetRepo.getArtifactDescriptors(mirrorRequest.getArtifactKey());
+		Assert.assertEquals(1, artifactDescriptors.length);
+		IArtifactDescriptor descriptor = artifactDescriptors[0];
+		Assert.assertNotNull("Signatures should be present",
+				descriptor.getProperty(PGPSignatureVerifier.PGP_SIGNATURES_PROPERTY_NAME));
+		Assert.assertNotNull("Keys should be present",
+				descriptor.getProperty(PGPSignatureVerifier.PGP_SIGNER_KEYS_PROPERTY_NAME));
 	}
 
 	@Test
 	public void testAllGoodWithEncodedProperties() throws Exception {
-		IStatus mirrorStatus = performMirrorFrom("repoPGPOK_encoded");
+		MirrorRequest mirrorRequest = performMirrorFrom("repoPGPOK_encoded");
+		IStatus mirrorStatus = mirrorRequest.getResult();
 		assertOK(mirrorStatus);
+
+		IArtifactDescriptor[] artifactDescriptors = targetRepo.getArtifactDescriptors(mirrorRequest.getArtifactKey());
+		Assert.assertEquals(1, artifactDescriptors.length);
+		IArtifactDescriptor descriptor = artifactDescriptors[0];
+		Assert.assertNotNull("Signatures should be present",
+				descriptor.getProperty(PGPSignatureVerifier.PGP_SIGNATURES_PROPERTY_NAME));
+		Assert.assertNotNull("Keys should be present",
+				descriptor.getProperty(PGPSignatureVerifier.PGP_SIGNER_KEYS_PROPERTY_NAME));
 	}
 
-	private IStatus performMirrorFrom(String repoName) throws Exception {
+	private MirrorRequest performMirrorFrom(String repoName) throws Exception {
 		// Clear the remembered keys/cache of the agent.
 		IAgentLocation agentLocation = getAgent().getService(IAgentLocation.class);
 		Path repositoryCache = Paths
@@ -84,14 +105,22 @@
 		ArtifactKey key = new ArtifactKey("osgi.bundle", "blah", Version.create("1.0.0.123456"));
 		MirrorRequest mirrorRequest = new MirrorRequest(key, targetRepo, NO_PROPERTIES, NO_PROPERTIES, getTransport());
 		mirrorRequest.perform(sourceRepo, getMonitor());
-		return mirrorRequest.getResult();
+		return mirrorRequest;
 	}
 
 	@Test
 	public void testMissingPublicKey() throws Exception {
-		IStatus mirrorStatus = performMirrorFrom("repoMissingPublicKey");
-		assertNotOK(mirrorStatus);
-		assertTrue(mirrorStatus.toString().matches(".*public key.*not be found.*"));
+		MirrorRequest mirrorRequest = performMirrorFrom("repoMissingPublicKey");
+		IStatus mirrorStatus = mirrorRequest.getResult();
+		assertOK(mirrorStatus);
+
+		IArtifactDescriptor[] artifactDescriptors = targetRepo.getArtifactDescriptors(mirrorRequest.getArtifactKey());
+		Assert.assertEquals(1, artifactDescriptors.length);
+		IArtifactDescriptor descriptor = artifactDescriptors[0];
+		Assert.assertNull("Signatures should not be present",
+				descriptor.getProperty(PGPSignatureVerifier.PGP_SIGNATURES_PROPERTY_NAME));
+		Assert.assertNull("Keys should not be present",
+				descriptor.getProperty(PGPSignatureVerifier.PGP_SIGNER_KEYS_PROPERTY_NAME));
 	}
 
 	@Override