My post before, about "Main Factor to Decrease the Google Page Rank" explain is PAID LINK will decrease your google pagerank.
This happened to many sites before, some of them penalize to zero.
But I try to find some information in google about Link Scheme and here what I got :
There are Link Scheme on google site as you can see below
"... However, some webmasters engage in link exchange schemes and build partner pages exclusively for the sake of cross-linking, disregarding the quality of the links, the sources, and the long-term impact it will have on their sites. This is in violation of Google's webmaster guidelines and can negatively impact your site's ranking in search results. Examples of link schemes can include:
- Links intended to manipulate PageRank
- Links to web spammers or bad neighborhoods on the web
- Excessive reciprocal links or excessive link exchanging ("Link to me and I'll link to you.")
- Buying or selling links that pass PageRank"
GOOGLE ALLOW PAID LINK
I found that google allow Paid Link, as google said :
"Not all paid links violate our guidelines. Buying and selling links is a normal part of the economy of the web when done for advertising purposes, and not for manipulation of search results. Links purchased for advertising should be designated as such. This can be done in several ways, such as:
- Adding a rel="nofollow" attribute to the tag
- Redirecting the links to an intermediate page that is blocked from search engines with a robots.txt file"
All that I know and what I will do now are :
- I will continue to Paid Link. Because I need more money to pay my internet connection (lol...)
- One of site which conformed violate google pagerank is Pay Per Post. So many articles expalin this
- I try to find what sites violate google pagerank, both Paid Post and Paid Link.
So... Your share about that are welcome...