Philips just released firmware for the Philips Hue bridge that may permanently sever access to any “non-approved” ZigBee bulbs. We previously covered third party support in January 2015, when Philips indicated it was not blocked – and have since benefited.
The recent change seems to suggest any non-Philips bulbs from manufacturers such as Cree, GE, and Osram will not be supported in many situations, whereas “Friends of Hue” branded product are. At the time of publication, it’s unclear whether 3rd party bulbs will stop working immediately after the firmware update or if they may only become inaccessible after the bridge is reset. We’re also not sure if being “reset” means rebooted or factory reset. This appears to apply to both the round v1 bridge and square v2 HomeKit-compatible bridge after the latest firmware update is applied.