If you work in an office, would they let you publish a book on your spare time? Obviously I'm not saying to write your book while you're at work; what I mean is even if you work on the book outside of working hours. I remember hearing about the Barbie vs Bratz legal battle because the guy that made Bratz was employed at the place that owned Barbie. And he actually ended up losing. So if I'm working at an office, would that be a problem?
I think that it's hugely "it depends". Depends, that is, on what contracts you might have signed, and how enforceable those contracts are in the relevant jurisidiction(s), and how closely related your work is to the writing that you want to publish, and whether your employer wants to be obstructive or cooperative. I believe that it's not at all un-heard-of for employers who have breathtakingly broad contracts claiming rights over your every creative thought, to nevertheless relinquish those rights when they're not relevant to the job. If you write code for video games, odds are your employer isn't interested in claiming the knitting patterns that you designed, especially if they're unlikely to be able to enforce that claim in court anyway. The better informed will no doubt provide better answers. However, you might want to start by digging through your employment paperwork, or talking to your HR department, to see if you did sign any contracts along those lines. ChickenFreak
Very unlikely that it would be a problem, Community, unless your day job involves the sort of artistic/creative endeavors that may be related to writing a novel. If you're just working a normal office job, your employer won't have any claim on your novel. In the Barbie/Bratz case the guy was found to have violated a copyright as well as a contract.
Unless you have a contract that specifically states that all your writing, while you are employed by them, is their property, you should be okay. Such a contract would be very unusual unless your day job involves creative writing (and probably unusual even then).