When you're building a prototype device, you usually tag everything and anything so you can track various problems. You might put 4-5 different batteries from different vendors in there to see which one performs better, or if one explodes you can track it back to the vendor and lot #.

So if this a prototype phone then yeah, you're probably gonna see labels and tags on it that you don't see on a production device. I'm not taking a side yet on if these photos are real, but in the CE world you see something like this a lot.