There are two major bitcoin heuristics to clustering an entity: common-input-ownership heuristic and change address detection heuristic. In a single transaction, common-input-ownership heuristic assumes the input address is all from one entity. There are cases, however, where input addresses can be of multiple entities. This is called coinjoin, and would break this assumption. (e.g. address 3 in the image below)
Introduction to Bitcoin Heuristics
Introduction to Bitcoin Heuristics
Introduction to Bitcoin Heuristics
There are two major bitcoin heuristics to clustering an entity: common-input-ownership heuristic and change address detection heuristic. In a single transaction, common-input-ownership heuristic assumes the input address is all from one entity. There are cases, however, where input addresses can be of multiple entities. This is called coinjoin, and would break this assumption. (e.g. address 3 in the image below)