I was under the impression that Monsanto, et al, own the seeds the sell. So they usually make it clear if they own the seeds so no one grows them without permission.
My 15 week old Buckeyes are in with the big chickens now and they are doing great without heat so far. Our coldest night was around 25 but much colder weather is coming. My 1, 5, and 7 week olds will have heat til they are at least half grown and I can wean them off of it.
Natural length of daylight is relative to where you live vs where chickens came from. If I wanted my chickens to have a completely natural life I would let them live in trees in the jungle. I use lights because we are far enough north to have very short days in winter. My chickens work here...