Most bloggers are grateful when their work is mentioned occasionally by a prestigious website that has recognized impact in informing the public. But when a blog is constantly mentioned by an obscure aggregator, then that could be damaging.
There are recognized websites that offer link aggregation of articles that are of value to readers in their respective fields. In the financial blogosphere there are a few such credible sources, the most well-known being Abnormal Returns and The Reformed Broker.
I am happy to get occasional mentions with links to my articles from these two aggregators just mentioned. It would be obviously silly from my part to expect to get a mention for each article I post in my blog. The individuals that run those services have a lot of experience and know what articles to select. If I manage to get a mention once a month or every two months then I consider that a great accomplishment from my part.
Now going into the technical details, it is important to understand that the websites mentioned are recognized by Google as credible aggregators with substantial blogoshere and community impact and they may not be required to designate links as a “nofollow”. Let me try to explain this in a nutshell:
When you post a link in your blog article, Google may perceive that as advertising and penalize you and the website you linked to by decreasing search rank. In order to avoid this, most aggregators use the following html tag: rel=”nofollow”. What this means is that although they include a link to your blog article, the search engine robots do not follow it and you do not get any rank credit for that.
Furthermore, some shady aggregators may use the work of other bloggers to promote their own articles and websites by linking to them without including the rel = “nofollow” meta tag in the html code. In this way they take advantage of the readers and followers of the other bloggers to massively promote their own work and increase their search engine rank.
I could go into more details but I know the audience is smart and this is probably plenty of information to start with. Google has this article with a reference to the “nofollow” meta tag. Note that after inserting the link to the Google article in the previous sentence I switched to text mode and inserted the “nofollow” meta tag.
You can inspect specific links for use of meta tags when using Chrome by right clicking on them and then selecting “inspect element”.
Shady aggregators can do a lot of damage to a website by limiting traffic and followers. If you feel that you have worked hard and you are not getting enough hits, or followers in Twitter, then it is highly possible that some shady aggregator gets all the credit. Readers just follow the aggregator and they think that is a credible source of information and articles when that website is maybe promoting own work and paid links while not providing any credit to links posted because of the use of the meta tag mentioned. Thus, the aggregator may be stealing your future while you are happy that they are posting links to your articles.
If you feel that some link aggregators are shady you should contact them and ask them to stop linking to your website. Not all that glitters is gold, remember that.