Air carrier Captain reported the planned DG report was issued but no DG final summary was received at departure time. After confirming with Dispatch that no DG had been loaded the DG form was generated as the flight departed.

Narrative

During preflight activities; a planned dangerous goods report printed. As our pushback time approached; we had not received a final dangerous goods report! We contacted the ramp; they didn't know that we had any dangerous goods. I then contacted dispatch to confirm if we had or didn't have any dangerous goods onboard. We agreed that it was unusual to get the planned dangerous goods report and not have any onboard! We spoke to ramp supervisors; load planners and controllers. None of them could confirm our situation. We then contacted the Chief Pilot to try and determine where the report gets generated. I don't think he understood what we were asking. As I didn't want to push not knowing for sure the status of the dangerous goods; the dispatcher and I requested documentation from the load planner and the ramp manager verifying that no dangerous goods were onboard! They did send these statements to me. The dispatcher and I then agreed that it would be safe to continue!After all this and a large delay to the flight; a final dangerous goods report was generated and printed as we departed!The flight was conducted without any incident!