The search engine marketplace underwent a number of changes in 2004 with the number of independent sources nearly tripling by year’s end. Twelve months ago, Google was the dominant search tool feeding information to almost every other popular search engine in one way or another, including its biggest rivals Yahoo and MSN. Going into 2005, Google still dominates the search engine market but the world’s most popular search tool has lost a great deal of ground to its former bedfellows. Yahoo introduced its own algorithmic search engine early last spring followed by MSN’s beta release of their own search tool in the autumn. Over the span of one year, Google’s control of organic results dropped from approximately 76% to the 45% share it owns today.

Google’s absolute dominance started about three years ago, a year before Yahoo purchased AltaVista, All the Web, Inktomi and Overture. At that time, Yahoo changed formats moving away from its original model of human edited directory listings in an attempt to emulate the success of Google. As it was unable to generate organic results on its own, Yahoo began to display results originating from the Google database. Yahoo, in turn, fed results to MSN. Realizing that getting great placements at Google virtually guaranteed strong placements at Yahoo and MSN, a Google-centric style of SEO emerged relying strongly on perceived PageRank values and heavy link-densities. To this day, search engine optimization forums are full of obsessive comments on back-link fluctuations and PageRank updates, even after Google openly admitted that PageRank, as measured by the Google toolbar should be viewed for entertainment purposes only.

It has been about three months since MSN released the beta version of their new search tool and nine months since Yahoo introduced theirs. Entering 2005, two of the Big3 control over 80% of the organic SERPs by displaying search results directly or by selling results to other search engines.

Google continues to be the number one distributor of search listings. Far and away the most popular of the Big3 with direct users, Google also distributes organic results to Netscape, AOL, HotBot, iWon, Go and Excite. Google is also the largest direct distributor of PPC results by providing paid-ads to Teoma, Ask Jeeves, About, Excite, Netscape, AOL, iWon, and Go. Indirectly, its AdSence program displays ads across more independent websites than all contextual advertising rivals combined.

Yahoo enjoys the second largest reach though the ownership of AltaVista, All the Web, Overture and the Inktomi database. Currently, Yahoo’s stable of search engines fees data to Excite, Hotbot, and the non-beta version of MSN, mostly through distribution of data from the Inktomi database. Yahoo also owns Google’s largest PPC rival, Overture which distributes paid contextual advertising to Excite, MSN, Yahoo, AltaVista and All the Web. Overture also distributes paid-ads across private websites, much like Google does through AdSence. Overture’s contextual distribution reach is however, eclipsed by Google’s. Oddly enough, Yahoo’s least known property, All the Web continues to receive organic results from its original parent company, FAST Search and Transfer, based in Oslo Norway.

Rounding out the list of well known search engines distributing data to other search engines is Ask Jeeves/Teoma and Lycos. Ask Jeeves is fed directly by Teoma and in turn feeds Excite and HotBot, which also purchases access to Lycos’ database of spidered sites. Lycos, incidentally, receives data from FAST Search and Transfer.

One can’t be blamed for needing a scorecard to keep up. Here is a link to an excellent animated search engine chart outlining which search tools feed which what.