Is this fairly common in the high-tech industry and do all big companies do this? (Amazon, Apple etc.) Would love to hear some personal feedback/stories.
At any large or mid-size high-tech company, there's usually a team of lawyers whose job it is to evaluate the work the company is doing and file patents on anything worth protecting. The bar for what can be patented is quite a bit lower than what most people expect (rounded corners? really Apple?), and so the general rule of thumb is "If you don't know for sure of someone who did the same thing, patent it." The onus is on the patent examiner to prove that the invention is not inventive, and so from the company perspective it is better to file everything and let the patent office sort out the mess. (Yes, this is deeply broken. If you care about fixing it, lobby Washington; the tech industry is just playing the game as the rules stand now.)
Many big companies give out bonuses for patents. These are usually a small fraction of the value to the company - judging by recent acquisitions, companies are valuing patents at close to a million dollars each, and a typical bonus is only a few $K - but they can be a nice source of extra change for an engineer. I know of people who've scrounged up the down payment for a house off their patent bonuses, and I once computed that on an hourly basis for work expended it works out to a few thousand dollars an hour, which is better than pretty much any other non-passive source of income.
Having patents on your resume is also a very good source of negotiating leverage when looking for another job. It's an externally-verifiable demonstration of innovation, which companies will pay much more for than when they think all you can do is follow orders.
This has been around for a long time. Indeed, there's a roughly similar story in Feynman's account titled "I Want My Dollar!":
> What had happened was, during the war, at Los Alamos, there was a very nice fella in charge of the patent office for the government, named Captain Smith. Smith sent around a notice to everybody that said something like, "We in the patent office would like to patent every idea you have for the United States government, for which you are working now. Any idea you have on nuclear energy or its application that you may think everybody knows about, everybody doesn't know about: Just come to my office and tell me the idea."
So Feynman pointed out to Smith there are a bunch of ideas and it's crazy to tell them all. He gives four examples, and leaves.
> About three months later, Smith calls me in the office and says, "Feynman, the submarine has already been taken. But the other three are yours."
> ... Anyway, Smith told me to sign some papers for the three ideas I was giving to the government to patent. Now, it's some dopey legal thing, but when you give the patent to the government, the document you sign is not a legal document unless there's some exchange, so the paper I signed said, "For the sum of one dollar, I, Richard P. Feynman, give this idea to the government . . ."
The rest of the story is about the $1, and how the other scientists, once they found how easy it was to get a dollar, started sending patent ideas.