The participating firms included Alison Brooks Architects from London, BIG Bjarke Ingels Group from Copenhagen, Cloud9 from Barcelona, Standardarchitecture from Beijing and J Mayer.
The dispute has blossomed into a battle as well over the design of the project, by Bjarke Ingels, a 38-year-old Danish architect whose futuristic designs often leave critics swooning.
Ingels uses a line by Google CEO Eric Schmidt about the ridiculousness of human-piloted cars and the inevitable carnage that has resulted from allowing so much potential for human error into the system.