Inter-RIR transfers refer to the process of transferring IP address space from one Regional Internet Registry (RIR) to another. This typically occurs when a company acquires IP address space from an entity registered with a different RIR. Inter-RIR transfers require the consent of both RIRs involved and may involve various fees. The process can take several weeks to several months, and each RIR has its own policies, procedures, and processes for such transfers. On the other hand, Intra-RIR transfers involve the transfer of address space within the same RIR and only require the consent of the receiving RIR. The approval process for an Inter-RIR transfer involves steps such as pre-approval, negotiation, and transfer request. The specific requirements and fees for Inter-RIR transfers vary among the different RIRs, including ARIN, RIPE, APNIC, and LACNIC.