Abstract: Can intellectual property public policies safeguard cross organizational digital innovation property rights and promote enterprise digital collaborative innovation? Based on the data of A-share listed companies from 2011 to 2023, this article takes intellectual property demonstration cities as a quasi natural experiment, uses jointly authorized digital patents to represent digital collaborative innovation, and tests the effects and mechanisms of intellectual property demonstration cities on digital collaborative innovation. Research has found that the construction of intellectual property demonstration cities promotes a 25% increase in the average digital collaborative innovation rate of enterprises, indicating that intellectual property public policies can help solve the problem of cross organizational digital innovation property rights and open up the channel for cross organizational "integration of data and reality". Heterogeneity testing found that digital collaborative innovation in the construction of intellectual property demonstration cities only has local creation effects, and spatial spillover effects are not significant; Weak foundations in digital innovation, experienced start-up growth stages, and "weak" enterprises such as private enterprises are more likely to leverage intellectual property public policies to give wings to digital innovation collaboration. In terms of mechanisms, enhancing the connection of multiple stakeholders, promoting the diffusion of basic research, and strengthening intellectual property law enforcement are all important mechanisms for promoting digital collaborative innovation among enterprises in intellectual property demonstration cities. The research conclusion provides theoretical guidance and practical inspiration for improving the innovation of intellectual property system and building a digital innovation consortium.