The LinkedIn Share Button module adds LinkedIn's new official share widget to your Drupal site. The module allows you to place the share widget on any content type that you have on your website and allows you to customize the button's display type.
Similar to the Tweet Button and Facebook share buttons, the LinkedIn Share button allows you to easily share your site's content with your LinkedIn network.
More information on the official LinkedIn Share Button
Image via: http://blog.linkedin.com/