Comment 8 for bug 1087873

the setting has changed in 13.10, it is now a declarative part of the .scope file. Online searching lenses have to declare themselves as being online lenses by using the RemoteContent=true flag in the .scope file. If that is set then those lenses won't be queried when the privacy flag is set. This is now documented in the tutorial.
http://developer.ubuntu.com/scopes/tutorial/
Please note that the default is false which is bug 1250134 so that a lens author who does not include that line will automatically be assumed to be a local lens and will be queried when the flag is set to local results only - so by default online lenses will still ignore the flag - but it is now declarative and external to the code of the lens, so this bug is fixed in Saucy.