There is an ongoing debate wether links have to be indexed to be counted (pass link juice) by Google. Unfortunately this debate is mainly anecdotal and I've not seen real proof from either side. Personally I do think they need to be indexed for several reasons beyond the scope of this topic, but I just realized there is an easy test to bring some scientific evidence in this debate.
- Why not copy the backlink profile from Webmaster Tools, run them through the Scrapebox Alive Checker and Check wether the alives are indexed. It's really that simple. Since the backlink data comes directly from Google itself, it means that if 100% of the backlink profile is indexed it shows definite proof these links have to be indexed to be counted!
If the number is below 100%, but let's say between 70-99%, there seem to be some other variabels going, but indexing does seem to be important. However, if the number is below -say 50%- we can argue that indexing might really not be that important. Sure, theoretically only the indexed links might be the ones passing link juice, while the other are just sitting there idle, but at least we tried.
Unfortunately I don't use Webmaster Tools on my SER sites to prevent footprints to my other sites (if I get a manual the domain is doomed anyway), but if someone does use WMT for his SER sites, please run this easy test and share your conclusions. If you don't have Scrapebox and feel comfortable sending me the data, I'm willing to do it for you.