Summary Box: Yahoo aims patent arsenal at Facebook

INTELLECTUAL RIFT: Yahoo is demanding licensing fees from Facebook. The reason: Yahoo believes its patented innovations help run Facebook's social networking service. If Facebook Inc. refuses to pay, Yahoo Inc. says it's prepared to sue.

CONTRASTING FORTUNES: While Yahoo's revenue has been steadily falling during the past three years, Facebook has been thriving.

THE STAKES: Yahoo could use a big payday to boost its sagging stock price. Facebook doesn't need a high-profile court battle that might dampen investor enthusiasm for an initial public offering of stock this spring.

Our goal is to create a safe and engaging place for users to connect over interests and passions. In order to improve our community experience, we are temporarily suspending article commenting