Update CONTRIBUTING.md

Author: cdsmith

CONTRIBUTING.md

@@ -4,18 +4,16 @@ How to contribute
 We'd love to accept your patches and contributions to this project.  There is
 just one thing you need to do first.
 
-Contributions must be accompanied by a Contributor License Agreement. This is
-*not* a copyright assignment.  It simply gives permission to Google to use and
-redistribute your contributions.
-
-If you are an individual writing original source code and you're sure you own
-the intellectual property, then you'll need to sign an
+All contributions must be accompanied by a Contributor License Agreement. This
+is *not* a copyright assignment.  It simply gives permission to Google to use
+and redistribute your contributions.  If you are an individual writing original
+source code and you are sure you own the intellectual property, then you'll
+need to sign an
 [individual CLA](https://developers.google.com/open-source/cla/individual).
-
-If you work for a company that allows you to contribute your work, then you'll
-need to sign a
+If you work for a company that allows you to contribute your work but retains
+copyright, then you'll need to sign a
 [corporate CLA](https://developers.google.com/open-source/cla/corporate).
 
 You generally only need to submit a CLA to Google once, so if you've already
-submitted one (even if it was for a different project), you probably don't
-need to do it again.
+submitted one (even for a different project), you probably don't need to do
+it again.