diff --git a/test/signatures.test.js b/test/signatures.test.js
index d37ae66..1ea3ee5 100644
--- a/test/signatures.test.js
+++ b/test/signatures.test.js
@@ -39,16 +39,72 @@ YCKJPotiqe50nBijHHbuABtBianiMZOm2BbaPnsmdHIX5ynWhOI8LHR1CVmTI/0o
 =2vuM
 -----END PGP SIGNATURE-----`
 
+const invalidSigProfileMessage = `-----BEGIN PGP SIGNED MESSAGE-----
+Hash: SHA512
+
+A demo signature profile for testing.
+
+proof=dns:doip.sucks
+-----BEGIN PGP SIGNATURE-----
+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+=2vuM
+-----END PGP SIGNATURE-----`
+
+const invalidSigProfileHash = `-----BEGIN PGP SIGNED MESSAGE-----
+Hash: SHA512
+
+A demo signature profile for testing.
+
+proof=dns:doip.rocks
+-----BEGIN PGP SIGNATURE-----
+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+=2vuM
+-----END PGP SIGNATURE-----`
+
 describe('signatures.process', () => {
   it('should be a function (2 arguments)', () => {
     expect(doipjs.signatures.process).to.be.a('function')
     expect(doipjs.signatures.process).to.have.length(1)
   })
-  it('should verify the demonstration signature', async () => {
+  it('should verify a valid signature', async () => {
     const verification = await doipjs.signatures.process(sigProfile)
     expect(verification.fingerprint).to.be.equal(
       '3637202523e7c1309ab79e99ef2dc5827b445f4b'
     )
     expect(verification.users[0].claims).to.be.length(1)
   })
+  it('should reject an invalid signature', async () => {
+    return expect(
+      doipjs.signatures.process(invalidSigProfileMessage)
+    ).to.eventually.be.rejectedWith(
+      'Signature could not be verified (Signed digest did not match)'
+    )
+  })
+  it('should reject an invalid signature', async () => {
+    return expect(
+      doipjs.signatures.process(invalidSigProfileHash)
+    ).to.eventually.be.rejectedWith(
+      'Signature could not be read (Ascii armor integrity check failed)'
+    )
+  })
 })