Cross linking websites of the same company, is it a good idea

[mcany]

As a user I think it is beneficial because those websites are segmented to answer to each customer needs, so I wonder if I should continue to do it or avoid it as much as possible if it damages rankings...

[TomRayner]

Hi Matthew

You'll probably be interested to see what Matt Cutts has to say about the issue: http://youtu.be/x0-jw_PfwtY

In short, a small number of sites that are related are fine to link to each other and won't flag quality guidelines.  It sounds like your websites fall under this, so you should be fine.

A problem may occur if there is a gratuitous amount of links or websites all passing PageRank.

If you want to be ultra-safe, you can make the links between the sites nofollow - which will you'll out any chance of a penalty due to interlinking.  But I think you'll be fine without this if done sparingly.

Hope this helps.

[simon_realbuzz]

I asked a similar question a few months back so some of the responses on this Moz thread will be of interest to you. Cheers.