meta tags apostroph and Quotation mark

Question

Some seo guy told me that I should not use apostroph in meta-tags, because it is not w3c conform. I tried with several doctypes, transitional, strict , html5... and got no errors shown.

<link rel='canonical' href='someurl' />

So what is right?

Answer 1

See the HTML5 CR, 8.1.2.3 Attributes.

There are four ways how attributes can be specified:

• Empty attribute syntax
• Unquoted attribute value syntax
• Single-quoted attribute value syntax (using ' (U+0027))
• Double-quoted attribute value syntax (using " (U+0022))

So yes, you may use '. In that case, the attribute value may not contain other ' characters (you’d have to encode them).