In light of the scattered nature of extant ecosystem literature, we seek to (1) identify the intellectual structure and theoretical roots of ecosystem literature within the broader field of innovation, and (2) take stock of how ecosystem research enriches and extends the innovation literature. Based on a bibliometric analysis of innovation and management journals over the past 30 years, we identify three lineages of ecosystem research within the “umbrella” of innovation studies. The first lineage finds its theoretical roots in the literature of product and architecture innovation. The second follows the lineage of open innovation and innovation strategy. The third adopts the traditions of regional innovation and entrepreneurship. Further, we offer an extended-boundary model that features two sets of synopses, explicating ecosystems' contributions to the field of innovation. The first set demonstrates how the ecosystem concept extends the three lineages with its unique attributes from a meta-organisational perspective, i.e., consumption-side synergies, boundary spanning and self-organisation. The second indicates how the concept may be repositioned on the foundational economic theories, i.e., Schumpeterian Innovation and Transaction Cost Economics, and advance how it may integrate the two schools and extend their research implications vis-à-vis profiting from, organising for, and outcomes of innovation. We contribute by organising the fragmented ecosystem literature into an integrative framework, forging stronger links with traditional innovation theories, and offering a cumulative theoretical basis for this promising concept to further flourish in the field of innovation studies.