I didn\'t post this on DocType because it\'s not really a design thing, the visual representation isn\'t my problem, the behaviour is. I\'m sorry if th
If you put a non-breaking space ( or \u00A0) or just a empty space (" ") between each span, it will separate the words and prevent the double-click selection from spilling into adjacent spans.
If you don't want to see a visible space, use a zero-width space (​ or \u200B).
I suspect that if you include a space or a non-breaking space   between your two elements, you will find that you can double-click, and select only one but not both elements, as the browser will no longer see the two elements as a single word.
I had the same problem. If you put a space before the closing tag of your li that should fix it.
<ul style="overflow: hidden;">
<li style="float: left;"><strong>SKU:</strong>123123 </li>
<li style="float: left;"><strong>ILC:</strong>asdasdasdasd </li>
</ul>