The Zend_View_Helper_HeadLink component uses shorthand tag closing notation on all link elements, regardless of the DOCTYPE provided to the Zend_View_Helper_Doctype component. I.e., it always produces elements like the following: Instead of the following: The current behavior is fine for documents written as XHTML, but not necessarily for HTML without the X; running such a document through the W3 validator (as, say, HTML 4.01 Strict) produces warnings and errors. This is a fairly trivial problem (since most browsers have no problem handling this kind of shorthand even in older flavors of HTML), but I think it would also be fairly trivial to fix (in fact, there's a good, simple precedent in lines 374-380 of the HeadScript helper), and doing so would make the framework's output more compliant with W3 standards (if only a little).