PostgreSQL license inquiry: source code disclosure obligations for commercial redistribution

Dear PostgreSQL Community,

We are considering using PostgreSQL as the database for a proprietary commercial software product. We would like to clarify the licensing obligations when distributing PostgreSQL together with our product for installation on customers’ servers.

Our application source code is intended to remain proprietary. We would appreciate your guidance on the following questions:

Commercial use and redistribution
If we modify PostgreSQL itself and distribute the modified binaries with our product, would we be required to disclose either the PostgreSQL modifications or our application’s source code?

Required notices
What copyright notices, license text, and disclaimers must accompany the redistribution? Would including the complete PostgreSQL License in a third-party license file supplied with our product satisfy these requirements?

Our understanding is that the PostgreSQL License permits commercial use and redistribution without requiring source code disclosure, provided that the required notices are retained. Could you please confirm whether this understanding is correct?

We understand that third-party drivers, extensions, and other bundled components may have separate licenses and should be reviewed independently. The questions above concern PostgreSQL itself.

If there is an official reference addressing these questions, we would appreciate a link for our internal compliance records.

I am not subscribed to this mailing list, so please CC me on replies.

Thank you for your time and assistance.

Best regards,
Jay Jeong