Accelerated innovation in climate-impacted oceans is outpacing standards of scientific responsibility. Standards of responsibility are critical because they shape research agendas, funding flows, scientific practice, and how innovations are regulated. Here, we examine responsibility debates among 243 marine scientists and end-users proposing, trialling and/or implementing 76 innovations for climate-impacted oceans. We identify three distinct discourses: ‘science outside society’, ‘science for society’ and ‘science with society’. Competition within and across these discourses reveals heightened tensions between the need to protect scientific autonomy and freedom, and moral duty to ensure socially just and desirable ocean futures. Without thorough debate and oversight, the wide-reaching power of such unresolved tensions could propel marine science and ocean futures into volatile ethical and moral territory. Better connection and articulation of standards of responsibility with scientific motivations, practices, and funding are key to ensuring the transparency and accountability required to progress equitable and sustainable oceans.