Why not? I mean this companies already have many parts of the car designed and built by third parties, there is no need to have everything designed and built b

Why not? I mean this companies already have many parts of the car designed and built by third parties, there is no need to have everything designed and built by themselves. So if you have 3 big companies collaborating you will have more money and maybe more important more training data for the self driving program. Now Uber,Tesla and Google do not share their data(probably the data is not compatible either) but if this data was shared progress could have been faster and lives could have been saved.