Yes! We catch them in the screening stage, but it's scarily common. I thought we were being targeted at first until I talked to other people with the same problem.

I've also heard of situations where one person is hired to do the job, but then after a while their work changes for the worse. They start "forgetting" things you've talked about recently, or they'll "forget" how the code they submitted an hour ago works.

They're either a front person for a dev shop, or they're trying to outsource their work. They don't care about doing a great job because they know most companies will take a long time to fire people. If the company PIPs them, they might suddenly become a great performer again until the heat dies down, then it's back to the same game.

Before the "if they're getting their work done, why does it matter?" comments: Having someone take our codebase and send it to random contractors is a huge security breach. Even ignoring that, these people aren't selecting world-class developers to outsource their work. They're outsourcing as cheaply as possible so they can pay as little as possible. It's never an okay deal for the company.