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This is strictly academic but I am having a friendly debate and I am hoping you guys could help me.  If I decided that I wanted to merge several websites into a single new URL doing everything I am supposed to (page to page 301 redirects, etc), will I still need to reach out to those important websites that link to my different sites to have them change the links and anchor text to point to the new site?  I know that 90% of the link juice is supposed to transfer and that you are SUPPOSED to contact linking domains, but is it really worth it, especially if there are literally hundreds of sites to contact?