The HTG doc plainly states to look for trafficking in the blue areas of that map.
https://www.sixdegreesofwikipedia.com/?source=Marina%20Abramovi%C4%87&target=Cemex
https://en.wikipedia.org/wiki/BuroHappold_Engineering
https://en.wikipedia.org/wiki/Arup_Group
https://en.wikipedia.org/wiki/Holcim
https://en.wikipedia.org/wiki/Scott_Wilson_Group
https://en.wikipedia.org/wiki/Serpentine_Galleries
https://en.wikipedia.org/wiki/Sharon_Hayes