BIP 159, found in BIP-159, suggested a way for nodes to advertise their willingness to provide filtering services like Bloom filters or BIP 158 compact filters. By including a dedicated service bit, nodes could signal, “I support advanced filtering—feel free to request partial block data.”

While the exact specification didn’t see broad adoption, it reflected the community’s intention to improve how nodes and SPV wallets interact. A universal advertisement method can streamline the discovery of filter-supporting peers, ensuring lightweight clients connect to the best possible nodes for efficient block retrieval.