Schema Markup for Organisation Logos
Yesterday Google announced that they launched a support for new type of schema markup, one for organisation logos. As described on their webmaster central blog, this new markup will help Google and other search engines pick your preferred logo to show in search results.
The implementation is simple and here is an example as shown on webmaster central blog:
<div itemscope itemtype="http://schema.org/Organization">
<a itemprop="url" href="http://www.example.com/">Home</a>
<img itemprop="logo" src="http://www.example.com/logo.png" />
This should be a string signal telling Google that this logo is the preferred logo, located at a certain designated location, that Google should use in search results wherever applicable. You can go to Schema Organisation markup to create logo or other markups for your site.