I'm pretty sure these are made to the specifications of the auto/engine manufactures. For instance, Ford's Motorcraft oil is made by ConocoPhillips and Korean S-oil. Many other brands are made by Warren in Canada.
Filters are a similar situation, but in my opinion, the quality of the filters are significantly better with the OEM brands. Well, all except AC-Delco. They seem flimsy to me. Standouts that come to mind are Motorcraft fuel filters, [AFFILIATE=1, nofollow=true, newwindow=true, title="Kubota"]Kubota[/AFFILIATE] hydraulic/transmission filters, and Honda engine oil filters. I have compared those filters with their Wix counterparts (which I tend to believe are decent quality) and feel that the media, housing (if applicable), and seals are all of better quality on the OEM parts.