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Below is the full text of a recent blog post that generates a lot of traffic, so it must be of interest to many.

"Does the parcel layer in Google Maps and Google Earth represent property lines?"

If I had a nickel for every time I have had to explain this to somebody…

There is an ongoing discussion among mapping professionals about the parcel data in Google Maps -- what this data layer represents, what the data source is, etc. At this point there are many unknowns, but one thing is certain -- these are not "property lines." Property lines, or boundaries, represent where a piece of property ends and the next one begins. A certain degree of accuracy is required for property boundary delineations. The accuracy of the Google Maps parcels in undeclared. As such, they cannot be construed to represent anything, really, much less "property lines."

[UPDATE 10:53 AM 03/14/2012] Several exchanges on the twitters helped me crystallize and fine-tune my point further. Which is: Mapping professionals know that the Google Maps parcel layer does not represent property boundaries. It is lay people who get confused. Due to its dominant position in search Google (unintentionally, I’m sure) conveys the expectation that the mapping (parcel) data they serve is authoritative, whereas in fact it is not.

Posted by Atanas Entchev at 3/14/2012 10:02 AM