Maturana the celebrated biologist and philosopher wrote that science was entirely "subject dependent" i.e. that it lay wholly in the domain of consensual subject interactions and required no metaphysical assumptions of an "ontic reality" beyond the existence of the observer.
Was he correct and if so what implications does this have for what we call "knowledge" ?
Yes, I think he was correct.
The implications to knowledge, as I see it, would be that knowledge too is "subject dependent". Meaningful only to the subjects it interacts between. "Knowledge" is a construction made up of concepts stacked on concepts in an intricate mix, and as such it is meaningful only to those who possess the same attributes and means of measurement as the entity that produced it.