Yahoo patents granted on 19 June 2012

4 US patents granted on 19 June 2012 and assigned to Yahoo

1 8,204,904 Network graph evolution rule generation
2 8,204,878 System and method for finding unexpected, but relevant content in an information retrieval system
3 8,204,874 Abbreviation handling in web search
4 8,203,952 Using network traffic logs for search enhancement