If Company A agreed to acquire Company B for $140 million last night, and Company A's stock gets shelled in after-hours trading to the tune of a $110 million hit to its market cap, does that mean the market thinks Company B was really worth only $30 million?

Not exactly.

Let's flesh out these unnamed widget havens to get to the bottom of things. Overture(Nasdaq: OVER) will dole out the bucks to buy AltaVista from fallen dot-com incubator CMGI(Nasdaq: CMGI). The Web portal has been swapped around like an Old Maid card over the years. It's an interesting family tree: AltaVista was the handiwork of Digital Equipment before a pre-Hewlett-Packard(NYSE: HPQ) Compaq absorbed Digital. While Compaq filed to take AltaVista public, the market conditions weren't right. In 1999, CMGI acquired an 83% stake in the search engine for a whopping $2.3 billion in stock and greenery.

Even adjusting for the dot-com bubble burst, it looks like Overture's getting a sweet deal on some high-traffic portal real estate. While it's no Google, AltaVista is still a popular online destination with nearly eight years of search technology. Yahoo!(Nasdaq: YHOO) is an $11 billion company, and Lycos was faring well before it was swallowed into Terra Lycos(Nasdaq: TRLY).

While it may appear to be a conflict of interest, Overture has made a profitable living by selling its paid search services to different portals. Owning one and the technology behind it won't change things, though Google may argue otherwise, as it arms itself with one more reason for sites to go with Google's newer yet similar performance-based AdWords Select offering.

That's fine. Let Overture's nervous sellers mark AltaVista down to nothing if they want to. The opportunistic buyers will get a proven dot-com success story with a well-traveled portal for free.