I’ve been looking into IP address filtering by content providers. I understand that IP addresses can be attached with confidence to geographical locations (at the country level, at least) about 80% of the time. You have to make up the rest with heuristics. So there are companies that are in the business of packaging those geolocation heuristics for sites.

Quova has a patent (No. 6,684,250) for

A method and an apparatus operates to associate a geographic location associated with a network address. At least one data collection operation is performed to obtain information pertaining to a network address. The retrieved information is processed to identify a plurality of geographic locations potentially associated with the network address, and to attach a confidence factor to each of the plurality of geographic locations. An estimated geographic location is selected from the plurality of geographic locations as being a best estimate of a true geographic location of the network address, where the selection of the estimated geographic location is based upon a degree of confidence-factor weighted agreement within the plurality of geographic locations.

Quova’s competitor Digital Envoy has a patent (No. 6,757,740) for

A method of determining a geographic location of an Internet user involves determining if the host is on-line, determining ownership of the host name, and then determining the route taken in delivering packets to the user. Based on the detected route, the method proceeds with determining the geographic route based on the host locations and then assigning a confidence level to the assigned location. A system collects the geographic information and allows web sites or other entities to request the geographic location of their visitors. The database of geographic locations may be stored in a central location or, alternatively, may be at least partially located at the web site. With this information, web sites can target content, advertising, or route traffic depending upon the geographic locations of their visitors. Through web site requests for geographic information, a central database tracks an Internet user’s traffic on the Internet whereby a profile can be generated. In addition to this profile, the central database can store visitor’s preferences as to what content should be delivered to an IP address, the available interface, and the network speed associated with that IP address.

Both of these issued in 2004.

Quova also has a 2006 patent (No. 7,072,963) for

A method and a system perform geolocation activities relating to a network address. A database of network addresses, and associated geographic locations, is maintained. A query, including a network address, is received against the database for a geographic location associated with the network address. Information, concerning the query received against the database, is logged. Geolocation activities relating to at least the network address are modified based on the logged information.

That’s pretty broad—a patent covering the modification of geolocation information based on queries.

So here’s the question: How widely are these services used? If they are in wide use (and I bet they are for advertising services), does it now make sense to put content sites to the burden of complying with the laws applicable to the people/machines they know are visiting them? Hmmm?

In the famous Yahoo! case, Yahoo! argued that it couldn’t know where people were coming from and that therefore it couldn’t block/filter usage of Yahoo.com based on geographical location. Is that still true? Google has its own geolocation heuristics. According to this press release, 35% of US online merchants were using geolocation tools as of the end of 2006.

All comments more than welcome.

(to find these patents, search this database)