Focusing on organizational ambidexterity is imperative for corporations to secure competitive advantage. To do so, start-up acquisitions help established companies complementing their internal innovativeness. Our survey with 116 start-up acquisitions shows how the acquired startup’s autonomy and functional integration impact the acquiring unit’s innovativeness. Interestingly, autonomy and integration can co-exist and are both positively associated with radical and incremental innovativeness. However, on a functional level we show that radical innovations are much more related to R&D autonomy, while incremental innovations are especially related to deep R&D integration. We hereby advance contradictions in corporate entrepreneurship research regarding the integration-autonomy dilemma and provide practical implications for managerial practice when it comes to new venture acquisitions.