Tips on dealing with illicit BGP announcements

[Randy Carpenter <rcarpen () network1 net>]

I am working with a client that has recently purchased and transferred an IPv4 block.

Sometime in between when the purchase and research was done and when the transfer was actually complete, an entity in 
Asia started illicitly announcing a larger block that includes the block in question. They even have gotten an RADB 
entry in place for it.

Does anyone have some tips on how to deal with this? I have a feeling that dealing directly with the offending entity 
will not be very fruitful.

thanks,
-Randy