There is a common practice among web developers to add a link to their own website on the bottom of every page of your site. Let me be direct here, there is not one good reason to do this. Not one.
Every time a link is added off of your site to any other site, it takes a bit of the search engine ranking "juice" away from your website to the other site. Some times this can be a good thing, if used in moderation. As an example if your site is about Rock and Roll music, and you link to the Rock and Roll Hall of Fame website, you are linking to an authority site and this can be a good thing because it is a related site and it is only one link. But when your web developer links to his own site, on EVERY page of your site, it is only benefiting them.
If your web person has done this, ask them why they have done this, and then insist that they remove it immediately. Sometimes developers will require this link and offer you a "discount" on their pricing. This is commonly referred to as BS. You should find a new web developer that actually has your business/website’s best interest in mind, not their own.
Net101 will never require a link from your website to our website, what we WILL do is link to your site from ours to help your ranking.