Nesting h3 inside anchor - how is this valid?

Question

<li class="vcard">
  <a class="url" href="/about/us/">
    <img class="photo" alt="some" src="/img/nicething.png">
    <h3>hello</h3>
  </a>
  <p class="role meta">Something here</p>
</li>

I've seen this code, I've validated and it returns VALID on w3c HTML5 validation.

I tough that we couldn't have h3 inside an anchor.

It seems that this became valid if we display:block; the anchor ?

Answer 1

If you look at the HTML5 spec, there is a section on the <a> tag:

The a element may be wrapped around entire paragraphs, lists, tables, and so forth, even entire sections, so long as there is no interactive content within (e.g. buttons or other links).

I can't find anything in the HTML4 spec that says that putting block-level tags inside of inline-level tags is invalid, but I do remember reading it somewhere.