I realize this thread is three years old now, but since I haven’t seen this solution posted anywhere, I thought I’d throw it out there for anyone who might come here looking for a way to integrate these bulbs into Smartthings. My husband brought a box of them home, not realizing that they weren’t compatible. Here’s how I got them to work with my setup, and depending on how you plan to use them (and if you don’t mind a little extra work), you may be able to get them to work too.
First of all, we use Alexa and Smartthings for just about everything. If you’re a Google Home or other user, read on and see if you can modify what I did to work for you. I turn lights, etc. off and on with Alexa spoken commands and the Smartthings app and routines. To get the C by GE bulbs to not only be seen in Smartthings and Alexa, but also to be controlled by either one and keep the status updated in both, start by enabling the C by GE skill within your Alexa app. Then pair the bulb with Alexa. Give it a name, for example Nightstand Lamp. Next, create a simulated switch and contact sensor in Smartthings (do this through the Smartthings dashboard, not the app - google it if you need instructions). It can’t just be a switch, it has to be both a switch AND contact sensor, because Alexa routines can’t be triggered by switches alone. Using our example, name this device Nightstand Lamp (VD). VD stands for virtual device, to distinguish it from the actual device. This is important because both devices will show up in Alexa and you need to be able to tell the difference. Then go into your Alexa app and create 4 routines: 1) when Nightstand Lamp (VD) contact opens (power on), turn Nightstand Lamp on; 2) when Nightstand Lamp (VD) contact closes (power off), turn Nightstand Lamp off; 3) when I say “Alexa turn on the nightstand lamp,” power on the Nightstand Lamp (VD) and 4) when I say “Alexa turn off the nightstand lamp,” power off the Nightstand Lamp (VD). Now whenever you ask Alexa to turn the light on or off, its status will be updated in Smartthings, and whenever you use the Smartthings app or routines to control the light, its status will likewise be updated in Alexa.
A couple of caveats to this approach - we do have a C by GE smart plug with smart bridge (https://www.amazon.com/gp/product/B07NNV4MHS) which I believe acts as a Hub for the C by GE products. Not sure if this is required for this setup or not, but I thought it worth mentioning. Secondly, I don’t ever control the C by GE bulbs from within the Alexa app. Obviously if you do, make sure you’re controlling the VD device, not the actual bulb, otherwise the status will no longer be synced with Smartthings. That goes for turning off a group of lights too. Just make sure the group includes the VIRTUAL device, not the actual device.
Lastly, in the interest of full disclosure, I actually created 6 routines in Alexa, to account for variations in asking to turn the light on and off: “Alexa, turn the nightstand lamp on” vs. “Alexa, turn on the nightstand lamp.” etc. So that’s 6 Alexa routines for each bulb. Multiply that by 4 bulbs, and well, that’s a lot of routines. But the trade off is that I get to use the bulbs with my Smartthings app, routines and Alexa. For that matter, you could use this approach for any smart device that can be seen by Alexa and not Smartthings. Hope this helps someone else.