You don't have to pay for ISO to implement an ISO standard. In addition, Oracle released their database software in 1979 but SQL only became an ANSI standard in 1986 (and an ISO standard in 1987) so they did originally reimplement an API which wasn't a public standard.

I'm pretty sure that a fair number of commonly used QR libraries were not developed by people who shelled out for a copy of ISO 18004 (they probably just looked at descriptions of how it works outside of the standard document). Similarly, you can implement your own SQL dialect without needing to read the ISO standard for it.

Yes if you want to be certified and want to get a copy of the standards document you'll need to pay, but it's not necessary (and I doubt that Oracle did, given that they implemented SQL before the standard existed and probably were involved in drafting it).

I'm not disagreeing with the validity of ISO or anything like that, I don't know where you got that impression.

The original point being made in this thread was that Oracle copied the API of SQL from IBM and thus is guilty of the same thing that they are accusing Google of doing. The counter-point was that SQL is an ISO standard and Oracle (allegedly) licensed it, which was then followed up by my point about Oracle DB predating the ISO standard. Hence why ISO is being discussed and why I was making the point that buying a standard document from ISO or paying for certification are not really relevant to this discussion.