Google Tests Search Refinement With Brand Filters

Google seems to be testing a new set of search refinements that let you filter by the brand or specific store you want to filter your results by. So a search for a [camo backpack] has search refinements for colors and size and type but also to let you filter by results on Amazon and Walmart, for example.

SearchEngineRoundtable1?d=UCg8P nGCaA | Craig Hordlow SearchEngineRoundtable1?d=yIl2AUoC8zA | Craig Hordlow SearchEngineRoundtable1?d=hl8ANDcrVaY | Craig Hordlow SearchEngineRoundtable1?d=V t1I SPZMU | Craig Hordlow SearchEngineRoundtable1?d=Gu391qSwH A | Craig Hordlow SearchEngineRoundtable1?d=cGdyc7Q 1BI | Craig Hordlow SearchEngineRoundtable1?i=4Bq3d2myUEQ:t025S1JbQXU:V sGLiPBpWU | Craig Hordlow SearchEngineRoundtable1?i=4Bq3d2myUEQ:t025S1JbQXU:F7zBnMyn0Lo | Craig Hordlow SearchEngineRoundtable1?d=MbsSfiz sEw | Craig Hordlow SearchEngineRoundtable1?d=qj6IDK7rITs | Craig Hordlow

4Bq3d2myUEQ | Craig Hordlow