alt Hacker News> For the same reasons and in the same way, those ideas — that intellectual property — belong to the company.
No, it's for fundamentally different reasons.
Physical property rights exist to protect people.
IP rights exist to benefit society other than the IP rights holders - either by a) incentivizing inventions (patents, that expire) or b) incentivizing creative works (copyright, that expire) or c) trademarks (that explicitly exist to prevent consumer confusion).
"Processes" and "techniques" that aren't patentable don't "belong" to a company with a factory in any legal or moral sense, and if they are patentable, they only belong to the company for the defined term of the patent, after which they belong to the public via public domain.
> (copyright, that expire)
For all practical purposes, copyrights no longer expire.
Any creative work made in your lifetime is unlikely to enter the public domain within your lifetime unless it was made during your childhood, the author holds the copyright rather than assigning it to a corporation, and the author already has one foot in the grave at the time of its creation.
Average US life expectancy is 79 years, humans develop their capacity for memory between 3-7 years, and copyright in the US lasts for 70 years after the author dies, so any creative work you'd remember from your childhood will only enter the public domain in your lifetime if the author dies within 2-6 years of creating it.