They're basically scanning your site for pages/sites you link to, and displaying data to their subscribers; it's likely not much benefit to you or your site, but to advertisers or your competitors it could be an SEO marketing tool.

It won't affect your search engine ranking anywhere to ban them, and may even speed up your site by not having them wasting your bandwidth for their service that you'll likely never use.

I am a Web Development Contractor, I do not work for UBBCentral. I have provided free User to User Support since the beginning of these support forums.
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