Most likely it goes far beyond that. California does have explicit provisions that protects your contributions outside of working hours, if done on your own hardware, and if they are unrelated to what your company is doing. Other states don't.

A good reading that covers this very topic really well: https://www.joelonsoftware.com/2016/12/09/developers-side-pr...

If you work at Google then that clause protects you much less than you'd think.

At Google (and most big companies, I believe), the rules apply to all work, not just working hours.

Joel Spolsky has a good article explaining the rationale:

https://www.joelonsoftware.com/2016/12/09/developers-side-pr...

How can something I wrote off-hours be the product of my employer? What if I 3D print a new window at my house? Is that also my employers product?

FTA:

>Suppose, now, you have a little game company. Instead of making software, you knock out three or four clever games every few months. You can’t invent all the games yourself. So you go out and hire a game designer to invent games. You are going to pay the game designer $6,000 a month to invent new games. Those games will be clever and novel. They are patentable. It is important to you, as a company, to own the patents on the games.

>Your game designer works for a year and invents 7 games. At the end of the year, she sues you, claiming that she owns 4 of them, because those particular games were invented between 5pm and 9am, when she wasn’t on duty.

>Ooops. That’s not what you meant. You wanted to pay her for all the games that she invents, and you recognize that the actual process of invention for which you are paying her may happen at any time… on weekdays, weekends, in the office, in the cubicle, at home, in the shower, climbing a mountain on vacation.

That thought experiment sounds off to me. What does "paying to invent" mean, exactly?

Presumably the employer wouldn't be happy if the designer simply had a bunch of nice design ideas and kept it in his or her head.

Instead, the designer should at some point write those ideas down and hand them over as a design document to the rest of the company. That process can provably happen during work hours, and the contents of the design document should be subject to the employment contract - since that's what the employer is paying for.

The document could, for example, have a boilerplate legal heading with "I declare all the contents herein are the sole IP of $company" or some such. Or the contract could specify that any document produced during work hours should satisfy such requirements. That would seem a safer legal protection than simply asserting the right to what the designer came up with on the previous day.

After all, if the concern is that the employee could have invented the game in the evening and then submitted it during the day - well, he or she could just as easily have invented it before their employment began and submitted it afterwards, no?

And it's worth noting much of this is fairly standard boilerplate at most shops nowadays.

Personally, I use it as a gauge of trustworthiness of employers; I am more than understanding that if I come up with a great idea related to something I'm working on, it's probably a result of the experience I've had AT that employer and it makes sense that they have some claim to that.

However, when employers say that ANY idea I have is theirs, that's usually a bad sign.

This is one extreme case caricaturized by the article, which is more nuanced.