Behind a proxy that is (optionally) configured to share this - yes. But what of a NAT[1] gateway.. most home (and many business) networks NAT your connection - to the destination server, all devices in that network have the same IP (or the IP is seemingly very dynamic if measuring hash(agent+ip)). Other than a server or a mobile-device on network data (assuming they aren't using IPv6) an IP will almost always represent a cluster of devices.

[1]: https://en.wikipedia.org/wiki/Network_address_translation