This paper uses patent data from the U.S. Patent and Trademark Office to investigate the implications of inventor collaboration and joint assignee ownership, both domestic and international, on patent quality as measured by the number of claims and citations associated with a patent. Specifically, we compare the quality implications of research collaboration and joint ownership for the quality of U.S. and Chinese patents. Overall, we find that domestic inventor collaboration yields higher quality results for U.S. patents than Chinese patents. However, for China, international collaboration, both for inventors and assignee ownership is associated with higher quality outcomes for Chinese patents than for U.S. patents. We also find that the incidence of inventors sharing assignee ownership is significantly higher in China. We hypothesize that this difference reflects a need in China to extend patent ownership to inventors for the purpose of recruiting and incentivizing a relatively limited supply of high-quality researchers, whereas in the U.S. the abundance of such researchers is retained largely through wage and bonus compensation.