Platformization is gathering pace because it is capable of restructuring the value creation process for ecosystems. Despite its merits, the failure rate of platformization is alarming for incumbents because it demands collective commitment from ecosystem partners who are already intricately connected due to their embeddedness in pre‐existing value networks. Consequently, the question of how incumbents can prepare for platformization has attracted attention from both academics and practitioners alike. By conducting multiple case studies of three distinct ecosystems that have successfully embraced platformization, we arrive at three separate process patterns of preparation for ecosystem platformization that elucidate the dimensions of organisational readiness required of the initiating firm and its partners. Particularly, we delineate between shared readiness and situated readiness, each with its own constituent sub‐dimensions underlying ecosystems' preparedness for platformization.