This study explores partnership formation dynamics between startups and corporations. The literature on strategic alliances has placed significant emphasis on establishing a "fit" between internal organizational strategy and external resource needs. However, our research indicates that in the context of corporate-startup corporations (CSCs), this “fit” is rather co-constructed than evaluated in advance. Drawing from extensive fieldwork observations of 150 “first meetings” between corporates and entrepreneurs, we find that interest in collaboration is driven by the interplay between technology, adaptability, and alignment. Adopting a configuration approach and employing a fuzzy-set qualitative comparative analysis (fsQCA), we uncover three unique patterns through which startups can secure interest from a corporation to collaborate. Contrary to the conventional strategy of matching startups based on how well their solution align with corporate needs, we advocate for establishing the right meeting conditions so that both parties can co-create mutually-beneficial collaboration opportunities. Taken together, our study underscores the fluid nature of corporate-startup relations, with interest in collaboration being (re)defined as the partnership formation process unfolds.