Will my association's network of sites get penalized for link farming?

[DigitalElevator]

Before beginning I found these similar topics here:

• http://www.seomoz.org/q/multiple-domains-on-same-ip-address-same-niche-but-different-locations
• http://www.seomoz.org/q/multiple-domains-on-1-ip-address

We manage over two dozen dental sites that are individually owned through out the US. All these dentists are in a dental association which we also run and are featured on (http://www.acedentalresource.com/). Part of the dental associations core is sharing information to make them better dentists and to help their patients which in addition to their education, is why they are considered to be some of the best dentists in the world. As such, we build links from what we consider to be valuable content between the sites.

Some sites are on different IPs and C-Blocks, some are not. Given the fact that each site is only promoting the dentist at that brick and mortar location but also has "follow" links to other dentists' content in the network we fear that we are in the grey area of link building practices.

Questions are:

1. Is there an effective way to utilize the power of the network if quality content is being shared?
2. What risks are we facing given our network?
3. Should each site be on a different IP?
4. Would having some of our sites on different servers make our backlinks more valuable than having all of our sites under the same server?
5. If it is decided that having unique IPs is best practice, would it be obvious that we made the switch?

Keep in mind that ALL sites are involved in the association, so naturally they would be linking to each other, and the main resource website mentioned above. Thanks for your input!

[benjaminspak]

"Part of the dental associations core is sharing information to make them better dentists and to help their patients which in addition to their education, is why they are considered to be some of the best dentists in the world. As such, we build links from what we consider to be valuable content between the sites."

Don't worry about all of that. Sounds like you guys are squared away ^_^