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I'm talking to a recruiter from a big IT company and in the last email she asked me to provide names of other companies that I'm interviewing with, as well as their location. What is the purpose of such question? Is it common practice? Should I answer or not?
I understand the point of asking general questions like 'Are you interviewing with other companies?', 'Do you have any deadlines?' and I'm answering them happily, but I've never been asked to provide any details regarding those companies. Answers to other questions (here and here) suggest to not mention names of other companies to recruiters, but don't provide any details on reasoning why.