So who gets the rights to a new gene-editing tool that can cut DNA strands and allow scientists to play god? Two influential universities — the University of California and the Massachusetts Institute of Technology are in a pitched battle to decide.

The fight involves what are known as CRISPRs (short for clustered regularly interspaced short palindromic repeats), which are DNA segments that have short repetitions of certain base sequences. Scientists can alter the DNA by changing the sequence around, and UC Berkeley found a way to do this with bacteria in 2012, turning it into a gene-editing tool, according to a San Jose Mercury News report.

They probably thought they had a lock on the patent — but they were wrong. Seven months later, researchers at MIT and Harvard found a way to do the same thing, but with human cells, and MIT paid an extra fee in order to expedite the patent and jump ahead of UC even though they filed at first. Now, MIT owns the patent that covers CRISPR in everything except bacteria, including humans.

Additionally, MIT said that UC’s method only worked on bacteria cells and had not been proven to work on humans, and the MIT scientist behind the work, Feng Zhang, submitted pictures from lab notebooks to prove that his work had made more progress.

However, UC hit back, submitting thousands of pages of documents to the U.S. Patent Office to argue that they were in fact first. The Patent Office has yet to weigh in on the matter or say whether they plan to reopen the case.