This has happened to me in the past. Many companies find it is too expensive to keep their mailing lists up-to-date so they just keep sending out junk mail to the old address.Here s what I did - if it s junk mail, toss it in the big round circular filing cabinet . If it looks personal or important, write Moved - No Forwarding Address - Return to Sender on it and give it back to the USPS. I figure if the previous owner really wanted that mail, he would have contacted the sender with a new address by now.
Best thing is to write RETURN TO SENDER on those and pop in the mailbox. Then the sender will get the message.