American research universities are increasingly coming under cyber-attack, with millions of hacking attempts every week, most of which are thought to be from China.

According to an article from The New York Times, campuses are forced to tighten security, constrict the culture of openness and try to determine what information has been stolen. University officials have conceded that some hacking attempts were successful, but they decline to reveal specifics. They acknowledge, however, that they frequently do not learn of break-ins until much later, if ever, and it might not be possible to tell what was lost.

Universities and professors are awarded thousands of patents annually, some with major potential value (prescription drugs, computer chips, fuel cells, medical devices). The number and sophistication of attacks are outpacing the universities’ ability to respond, the article reports.

Officials do note that hackers have become adept at bouncing their work around the world to avoid detection; university personnel do not know whether the attacks are private or governmental, the article says.

The increased threat from hacking has forced some universities to rethink the basic structure of their computer networks and their open style. Some universities no long allow professors to take laptops to certain countries. However, compared with enterprise companies that also must protect intellectual property, universities’ networks pose a unique problem: they are built for collaboration between people and often between institutions, plus, thousands of faculty and students log-in every day.

At Perdue, the most sensitive data is most carefully guarded, separated out from the rest of the university’s access and protected with stronger data encryption. Sometimes, the data is not even connected to the larger campus network, especially when the work involves dangerous pathogens or research that could turn into weapons systems, the Times reports.

At the University of California, Berkeley, millions of attempted break-ins weekly caused the school’s cyber-security budget (already in the millions of dollars) to double in the last year.