My current job is with Company A. Before that, I was with Company B, an on-site contractor for Company A. So after I'd worked there for a while as a B-employee, Company A hired me directly.
Now I'm filling out an online job application, and for each previous job it asks for a contact, phone number, and:
May we contact this employer?
I am planning to answer "no" for my current employer, as I don't want them to know I'm interviewing elsewhere. (I'm not even actively looking, this opportunity was just too good to pass up!)
My problem is that my manager for Company B sits in the same office as my current manager. He also has limited privacy, so I'm concerned about someone overhearing while they refill their coffee and word getting out.
Under the circumstances, I would rather they did not contact him, but I've heard saying "no" to contacting previous employers is a red flag. The job application form does not provide a space where I could explain.
What's the best option here? Should I provide an HR contact instead? (They are in a separate office, but don't know anything about what I did, beyond my job title.) Or just give a heads-up to my former manager and ask him to be discreet if they call?