In the past I've worked with recruiting agency A. Today I was contacted by recruiter B, whom I knew through recruiting agency A but has now left and is now working for recruiting agency C. The conversation was mostly amiable and normal, except that he asked a couple of times that I keep our dealings hush-hush from agency A. That raised warning bells with me, just because trying to keep things hushed-up can mean that something inappropriate is happening. My suspicion, or best guess, is that B is using some information in violation of agency A's confidentiality or non-compete agreement. I know that not all legitimate job endings leave on friendly terms, but I'm having a little difficulty thinking of a legitimate reason why he would contact me after knowing me through agency A and then ask that I keep his contacting me hushed-up from agency A.
First of all, is this suspicious, in line with my guess-work, or are there straightforward and perfectly believable reasons why B would contact me while working for C and ask me to keep this a secret from A?
Second of all, where do I go from here? Has he shown himself a breaker of trust? Is this a regular recruiting relationship which I should take at face value? Is it something else? What should our dealings (if any) be from here?