10 days ago, there were 3 companies sending me email about the job opportunity. But the interview schedule took more than 4 days until I pushed them with a few emails. The strange thing is that 3 confirmation email arrived almost the same time, around 9:00PM PDT. But the time on email were 10 hours early, around 4:00AM tommorow. All 3 emails have the same similar time stamp. I would doubt there is a coordinator behind.
A few years ago, Microsoft sued Google because Kaifu Li switched from Microsoft to Google. finally there was a secret agreement. I guess that agreement is about the hiring process.