Share Link to Facebook...clarification of TOS

Hi,

I was wondering if you could help me with this...I post my photography on a site that have recently added share link buttons to Facebook/Digg/Reddit/Twitter. My question is about the share link TOS (below) on Facebook. Specifically No. 2. And the definitions that they use, also copied below.

"Special Provisions Applicable to Share Links

If you include our Share Link button on your website, the following additional terms apply to you:

1. We give you permission to use Facebook's Share Link button so that users can post links or content from your website on Facebook.
2. You give us permission to use such links and content on Facebook.
3. You will not place a Share Link button on any page containing content that would violate this Statement if posted on Facebook."

"Definitions

1. By "Facebook" we mean the features and services we make available, including through (a) our website at Welcome to Facebook | Facebook and any other Facebook branded or co-branded websites (including sub-domains, international versions, and mobile versions); (b) our Platform; and (c) other media, devices or networks now existing or later developed.
2. By "us," "we" and "our" we mean Facebook, Inc. and/or its affiliates.
3. By "Platform" we mean a set of APIs and services that enable applications, developers, operators or services to retrieve data from Facebook and provide data to us relating to Facebook users.
4. By "content" we mean the content and information you post on Facebook, including information about you and the actions you take.
5. By "post" we mean post on Facebook or otherwise make available to us.
6. By "use" we mean use, copy, publicly perform or display, distribute, modify, translate, and create derivative works of."


My question is, the share link button is situated on every page that I have a piece of artwork. If pressed by anyone (member/non member of the site that hosts my work) it creates a thumbnail - of the specific piece - link on that persons facebook page. Although the thumbnail isn't hosted on facebook, do facebook gain a license to use my work as per the terms above? I know the terms are vague but alarm bells are ringing for me because I see no language such as "for the sole purpose of display on facebook..." etc., etc.

Any help would be much appreciated.

They do yes but it seems as a practical matteer that is limted to the link context--they are not going to go out and sell your work, and if they did that would violate the spirit of the agreement/terms.