Should I use nofollow when interlinking large, networked sites?

[Natasha9004]

My company runs a network of very large networked sites, each with thousands of content pages. In our main navigation we are currently not nofollowing links between these networked sites. The links appear on every single page in the top navigation, and there are thousands of pages on each site.

I am worried this will look to Google like we have suspiciously received thousands of links from one domain - one link from every page on the domain.

Should we be nofollowing these navigation links between the different sites in our network?

[William.Lau]

First off, I would think to myself what is the reason we are linking them all to.
If the reason is good enough to cross link the sites together, I'd nofollow them.

Sitewide links have been proven to be a bad option and if it is a must, I'd nofollow them.

[MoosaHemani]

Although I do agree with Google but talking form the personal experience unless you are a BIG brand sitewide links are going to kill you no matter how valid they are on your website and visitors...

Try to avoid as many sitewide links as possible!

[Doc_Sheldon]

I'd agree that sitewides should be avoided whenever possible. It sounds as though you may be flirting with disaster. If it were me, I'd nofollow them, at the least.