This excerpt taken from the SOHU 10-K filed Feb 28, 2006.
We rely on our Website Alliance members for a significant portion of our revenues. If we fail to retain existing Website Alliance members or attract additional members, our revenues and growth may be adversely affected.
By posting bid listing links on their Websites, we share with our Website Alliance members the revenues generated from clicks by users. For the year ended December 31, 2005, the total revenues generated from Website Alliance accounted for 81% of our total bid listing revenues. We consider our Website Alliance critical to the future growth of our revenues. If our Website Alliance members decide to use a competitors or their own Internet search services, or if we fail to attract additional Websites to join our Website Alliance, our sponsored search revenue may decline.