A memo written by a former Google engineer claims that senior executives at the company intervened to stop employees discussing matters involving diversity and hiring policies.

The memo, written in 2016 and shared publicly this week on Google Docs, is the work of former Google security engineer Cory Altheide, according to a report from Gizmodo. Altheide was employed by Google between 2010 and 2016, and says he chose to leave after confrontations with executives and HR over the posting of pro-diversity comments and articles in internal discussion groups.

The memo is titled “What happened to Cory?” and was originally written as an explanation of his departure to co-workers. In it, Altheide says that from July 2015 he participated in a “sadly contentious” internal thread discussing the “pipeline problem” in tech — the idea that tech companies don’t hire more inclusively because of a lack of available talent.

Altheide says that two Google executives, senior VP of technical infrastructure Urs Hölzle and senior VP of ads and commerce Sridhar Ramaswamy, got involved in the thread to try and calm the discussion. The thread reportedly stopped when Ramaswamy posted the following message:

As both the tech diversity lead at Google and someone who cares deeply about our workplace culture, I respectfully ask that everyone stop engaging on this thread. [Emphasis his.] While there have been some great ideas and stories shared here, this thread as a whole has turned negative rather than constructive. Google is not a debate club or a philosophy class. We are a workplace and we have an obligation to make sure our discussions remain respectful. Debates around topics like product excellence can support a wide variety of viewpoints and are great to have. I don’t think the same can be said for debates around sensitive issues such as gender, religion, race, or sexual orientation.

In September that year, Altheide started a new email chain titled “Just Asking Questions,” which he says was intended to highlight the fact that some Google employees may not be discussing questions of diversity in good faith. As evidence, he linked to external blogposts allegedly written by a Google employee that espoused views like “Blacks are not equal to whites. Therefore the ‘inequality’ between these races is expected and makes perfect sense.”

Later in the month, Altheide says he was called into a video meeting by a “HR business partner.” When he joined the call, though, senior VP Hölzle was also present, and told Altheide he was there to discuss his “worrying pattern of posting topics that are divisive going back to 2013.”

“If the majority of your coworkers are Nazis, it is better if you don’t know about it.”

Altheide told Gizmodo that he thinks Hölzle saw his discussion as “rabble rousing.” He says that Hölzle’s attitude was one of “don’t ask, don’t tell,” and claims that the VP, who is Google’s eighth employee, told him: “If the majority of your coworkers are Nazis, it is better if you don’t know about it.” Altheide says he wrote this comment down verbatim after the meeting “because I thought it was a savagely tactless analogy for a Swiss man to be making.”

After these events, Altheide decided to leave the company in January 2016. “I’m leaving because I don’t trust Urs. I’m afraid of Urs. He inserted himself into what should have been a conversation with my direct manager, and ‘requested’ I stop doing talking [sic] about things he doesn’t want me to talk about,” he wrote in his memo.

Altheide’s account provides a counterpoint to the description of Google by former engineers James Damore and David Gudeman. Damore was fired from the company last year for writing a 10-page internal memo that claimed biological differences between men and women accounted for the predominantly male staff at Google. Damore and Gudeman are now suing the company for allegedly discriminating against conservative white men.

In an interview with Gizmodo, Altheide said: “The idea of trying to alter a company’s culture all by yourself is almost as stupid as the myth of meritocracy the tech industry is so in love with. The only way to even begin to attempt to create positive change inside an organization purpose-built exclusively for the task of providing value to shareholders is through collective action.”

You can read Altheide’s memo in full here. We’ve reached out to Google for comment and will update this post when we hear back.