From NoHatSeo: When getting your backlinks from offsite sources, be sure to check their who.is registration and make sure at least something is listed there and privacy is not set. I've checked this myself and saw significant increases on my test sites when I changed the who.is information and removed privacy.
Making sure all Whois contact information matches, besides billing and tech contact info, with your Privacy Policy and your Contact Us page seem like legit SEO recommendations, and make total sense.
Pretty simple test actually. I have about 10 test sites that I use just for algorithm testing. These are each linked to from a private blog network. One of these sites was used for the following test: Week 1: Test Site A is ranked at #29 and has 12 individual sites linking to it (all with private who.is) Week 2: Removed private who.is from 3 of the linking sites and added fake registration info (fake email, name, address, etc) Week 3: Changed 3 more : Week 5: All 12 linking sites now have privacy turned off. Now ranking #18 No changes were made to Test Site A except for the registration.