ZDNet has a list of 10 patents that Facebook is using to attack Yahoo. This is a simple list:

1. Generating a feed of stories personalized for members of a social network (U.S. Patent No. 7,827,208)
2. Tagging digital media (U.S. Patent No. 7,945,653)
3. Headline posting algorithm (U.S. Patent No. 6,288,717)
4. Method for enabling a user to fetch a specific information item from a set of information items, and a system for carrying out such a method (U.S. Patent No. 6,216,133)
5. Customizing database information for presentation with media selections (U.S. Patent No. 6,411,949)
6. System and method for dynamic profiling of users in one-to-one applications (U.S. Patent No. 6,236,978)
7. System and method for dynamic profiling of users in one-to-one applications and for validating user rules (U.S. Patent No. 7,603,331)
8. Architectures, systems, apparatus, methods, and computer-readable medium for providing recommendations to users and applications using multidimensional data (U.S. Patent No. 8,103,611)
9. System for controlled distribution of user profiles over a network (U.S. Patent No. 8,005,896)
10. System for controlled distribution of user profiles over a network (U.S. Patent No. 8,150,913)

Go to ZDNet for complete details of each patent. Other reading: Facebook countersues Yahoo over 10 patents.