When a Google recruiter emailed an Apple employee in 2007 about a possible opening, the late Apple CEO Steve Jobs discovered the email and quickly forwarded it to his counterpart at Google, CEO Eric Schmidt. “I would be very pleased if your recruiting department would stop doing this,” Jobs wrote.

In another email exchange that year, Schmidt told Intel CEO Paul Otellini, “If we find a recruiter called into Intel, we will terminate the recruiter. We take these relationships [between companies]exceptionally seriously.”