Depends on where you live and your company. In the US, the laptop is company property, and so is anything you produce on it barring some other agreement.
I think this is less true to an extent in Europe, where at least some countries establish privacy rights to employees when using company equipment- at least when it comes to Internet browsing history and private emails. I'm not sure if creative works like personal side projects would also be protected.
Really though, when it comes to using company time or property for personal gain, the only real answer is "talk to your lawyer".
from legal perspective definitely, usually its phrase "as long as its created during work time or with work equipment or its work related" its property of the company.
I am asking more from technical point of view, e.g. I guess the tech companies at least will have booting from usb blocked completely, or it triggers some bitlocker type lock
I'm not too familiar with big tech companies blocking booting from USB, though it is a pretty common practice in the finance sector, iirc.
There's an apocryphal story of a security researcher who was tasked by a bank to break in if he could. He littered CD's around the parking lot (or was it USB drives? I forget) back when auto-run was a thing. Employees saw the disks on the ground, picked them up wondering what they were, and inserted them in their work computers to find out. Tada! Access granted. As such, Big Corporate companies (finance, insurance, retail, etc) tend to lock down their computers pretty hard... tech companies less so, I think.
I think this is less true to an extent in Europe, where at least some countries establish privacy rights to employees when using company equipment- at least when it comes to Internet browsing history and private emails. I'm not sure if creative works like personal side projects would also be protected.
Really though, when it comes to using company time or property for personal gain, the only real answer is "talk to your lawyer".