Philips makes a line of "smart" LED lightbulbs and controllers called Hue, that run the Zigbee networking protocol, allowing third-party devices to control their brightness and color.
The latest Hue bridge firmware update locks out competitors' bulbs from manufacturers like GE. Other bulbs that Philips have approved are not locked out.
This will be familiar to anyone who owns an Ios device: the manufacturer installs code in a device that you own that prevents you from buying legitimate things from competing vendors and connecting them to your device. The difference here is that Philips is doing this with lightbulbs instead of apps, but the principle is the same: though you bought the thing, you don't own the thing, and it is designed to defy you when you ask it to do things that are not in its manufacturer's interest.
This parallel isn't just a theoretical one, it has important legal ramifications. Under Section 1201 of the DMCA (and its foreign analogs, such as Canada's Bill C11 and European laws that implement the EUCD) it's a felony to remove a digital lock like this one, even for a legitimate purpose (like deciding for yourself whose lightbulbs you want to buy).
Philips says they've done this to help their customers.
While the Philips Hue system is based on open technologies we are not able to ensure all products from other brands are tested and fully interoperable with all of our software updates. For guaranteed compatibility you need to use Philips Hue or certified Friends of Hue products.
Lightbulb DRM: Philips Locks Purchasers Out Of Third-Party Bulbs With Firmware Update