A deal between Google and one of the largest U.S. hospital networks is stoking privacy concerns, with some uncomfortable with the tech giant having access to patient’s names instead of anonymous data.

On Monday, news broke that Google and Ascension forged a partnership to share health data and technology services to help streamline physician practices. However, some observers objected to Ascension’s call to give Google full access to patient records — including their identities.

Zack Cooper, a health policy expert at Yale’s School of Public Health, said the practice of tech companies partnering with health providers — without the consent of patients — isn’t entirely unheard of.

However, he argued the arrangement shows how patient privacy may not be as air-tight as some think.

“I think we’ve historically tried to think of our health care data as somewhat different,” he told Yahoo Finance on Tuesday.

The search giant’s involvement is a concern, because “Google knows a lot more about me that’s sensitive, from my search history than they do from a medical record.”

‘Not a great reason’

Google’s deal comes as big tech companies like Apple (AAPL) and Amazon (AMZN) are moving quickly to make inroads into the health sector. The search giant’s recently announced deal to buy Fitbit — whose wearable devices capture vital user data — is just one example of the growing convergence between health and technology.

In a blog post, the company moved to blunt criticism in the wake of a Wall Street Journal expose. Google Cloud’s Tariq Shaukat explained that it was able to get access to legally-protected patient data because it had signed an agreement with Ascension, the country’s second-largest health system. Under the agreement, the data can only be used to treat patients.

Shaukat insisted that “Ascension’s data cannot be used for any other purpose than for providing these services we’re offering under the agreement, and patient data cannot and will not be combined with any Google consumer data.”

However, experts say the arrangement still raises certain questions. Without knowing the details of the arrangement, it is impossible to understand why patient names were included, whether the data will be monetized somehow — or who even owns the information.

On Tuesday, CNBC reported that some Ascension employees voiced concerns about the tools being used by Google, and whether they complied with federal privacy standards. A request for comment to Ascension from Yahoo Finance was not immediately returned.

Yale’s Cooper equated it to the use of a search engine or credit cards, which are regularly mined for more sensitive data. However, access to patient names seems unusual, he said.