Yes, it is possible to link addresses together and determine if they come from the same wallet or seed. This can be achieved through various methods, including on-chain data analysis and transaction graph analysis.
Here are a few techniques that can be used to link addresses:
1. Common Input Ownership: When multiple addresses are used as inputs in the same transaction, it suggests that those addresses belong to the same entity or wallet. By analyzing transaction inputs and outputs, patterns can be identified to link addresses together.
2. Change Addresses: Many wallets use change addresses to improve privacy and security. When a transaction is made, the change is often sent back to a different address within the same wallet. Analyzing the change addresses and their relationships to other addresses can help identify common ownership.
3. Cluster Analysis: By analyzing transaction patterns, such as common spending habits or recurring transaction flows, it is possible to group addresses together into clusters that are likely controlled by the same entity or wallet.
4. Heuristics and Metadata: Some analysis techniques involve using heuristics and metadata associated with addresses, such as IP addresses, transaction timestamps, or known wallet behavior. These can provide additional clues to link addresses together.
It's important to note that while these techniques can be effective in certain cases, they are not foolproof. Privacy-enhancing techniques like CoinJoin, mixing services, or using separate wallets can help mitigate the ability to link addresses together.
Additionally, newer technologies like Hierarchical Deterministic (HD) wallets, which generate a new address for each transaction, can make it more challenging to link addresses together.