diff --git a/.travis.yml b/.travis.yml
index bd60a9fb3..3177040ed 100644
--- a/.travis.yml
+++ b/.travis.yml
@@ -2,14 +2,14 @@ language: java
 sudo: false
 
 jdk:
-  - openjdk6
   - openjdk7
   - oraclejdk8
 
-# only build trunk
+# only build master and the MATH_3_X branch
 branches:
   only:
     - master
+    - MATH_3_X
 
 after_success:
   - mvn clean test jacoco:report coveralls:report