Because security researchers have to bypass Deere tractors' locks to probe their security, Deere can leverage DMCA1201 into a veto over who gets to warn the public about the mistakes it made.
It's not just security researchers that Deere gets to gag: the company uses its repair monopoly to threaten farmers who complain about its business practices, holding their million-dollar farm equipment hostage to their silence:
https://pluralistic.net/2022/05/31/dealers-choice/#be-a-shame-if-something-were-to-happen-to-it
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