Abstract: Open innovation is a paradigm that is based on the concept of availability of abundant knowledge outside the boundaries of organizations. This study identified the influence of degree of openness, strength of appropriability regime, and project management maturity on the performance of open innovation projects. Performance was measured based on reduction of technology transfer time from research labs to business units, time to market innovations from the business units, and degree of innovativeness of the outcome. Data from 92 open innovation IT projects across India and Europe were used to test the proposed hypotheses using multiple linear regression and binary logistic regression. We developed an index termed Partner Collaboration Intensity (PCI) to measure degree of openness based on number of partners, intensity of collaboration, and innovation funnel openness. Results showed that specialized research or market partners reduced technology transfer time from research labs to business units. Results also indicated higher values of PCI index, higher strength of appropriability regime, and higher levels of project management maturity positively influenced reduction of technology transfer time from research labs to business units. Results of the logistic regression model showed that all parameters except higher strength of appropriability regime had a positive correlation with the occurrence of breakthrough innovations compared with incremental innovations.