I have a total of 10 stock market related trading sites. All of the sites are intended to provide users with free daily stock picks. The content for all of the sites is the same except for the home page which is 100% unique from site to site. Of the 10 sites there is one main site that we use. Question 1; could Google be punishing me because I have duplicate content on all these sites? if so, what can I do? Question 2; I have read that cross linking can be looking down upon by google. The only "cross linking" that I am doing is having all of the sites link to site1.com. site1.com does not link back to any of the other sites. Is that OK?
Frankly I don't see why one would set up 10 identical sites (apart from the front page)... #1 No, Google will not punish you, just filter your duplicates. #2 Probably, yes.
If you have duplicate content, that is not the whole issue But keep adding fresh content and develop backlinks to those content and those duplicate contents as well This should keep you in green, but if you leave those sites there without any backlinks then over a period of time google will de-index them