diff --git a/.travis.yml b/.travis.yml
index 30dee4db5ce783bcc02bd2d9fef59b6e3c91337f..fafa9fc296d39328a43f5dd7cf6186b01117a48a 100644
--- a/.travis.yml
+++ b/.travis.yml
@@ -186,13 +186,13 @@ before_script:
     fi
     
   # Install signing cert into OSX keychain
-  - if [[ "${SPEC}" = "macx-clang" ]]; then
+  - if [[ "${SPEC}" = "macx-clang" && "${TRAVIS_PULL_REQUEST}" = "false" ]]; then
         export CODESIGN=codesign;
     fi
-  - if [[ "${SPEC}" = "macx-clang" ]]; then
+  - if [[ "${SPEC}" = "macx-clang" && "${TRAVIS_PULL_REQUEST}" = "false" ]]; then
         openssl aes-256-cbc -K $MAC_CERT_KEY -iv $MAC_CERT_IV -in deploy/MacCertificates.p12.enc -out deploy/MacCertificates.p12 -d;
     fi
-  - if [[ "${SPEC}" = "macx-clang" ]]; then
+  - if [[ "${SPEC}" = "macx-clang" && "${TRAVIS_PULL_REQUEST}" = "false" ]]; then
         source deploy/MacImportCert.sh;
     fi