Because the <head> tag of some HTML pages in the Java SE developer guides is badly formatted (or some other tag), the DOCTYPE string gets clobbered by scripts that add branding to the pages. As a result, part of the DOCTYPE string is rendered in the web browser.
Examples:
http://download.java.net/jdk7/docs/technotes/guides/net/
http://download.java.net/jdk7/docs/technotes/guides/jweb/mixed_code.html
Examples:
http://download.java.net/jdk7/docs/technotes/guides/net/
http://download.java.net/jdk7/docs/technotes/guides/jweb/mixed_code.html