Derivative work isn’t automatically allowed under copyright law regardless of whether you’re trying to “deceive” people or not.

Depends if it's sufficiently transformative or not.

That just means it’s then subject to its own copyright. It doesn’t mean that the derivative work is also exempt from the terms of the original copyright.

For example, you can use a sample in a new song. And that new song can by copyrighted. But you still have to seek permission from the copyright holders of the sample to use it.

Fair use is the only time it’s legal to use another copyrighted piece without consent. And the rules for fair use vary from country to county.

Seek? In the grand scheme of things asking forgiveness only applies if you're going to not be that transformative and something like YouTube's automated copyright strikes might affect you. "Ask Forgiveness" is often a better option.

Fair use is a defense, not a requirement - You don't need permission to claim fair use; it's a legal defense if you're sued Seeking permission can backfire - Copyright holders may deny permission even when fair use would apply, creating unnecessary barriers.

This is especially true for parody and commentary.

> Seek? In the grand scheme of things asking forgiveness only applies if you're going to not be that transformative

That’s not why I said.

> something like YouTube's automated copyright strikes might affect you. "Ask Forgiveness" is often a better option.

Now you’re talking about platform quirks rather than copyright law.

> Fair use is a defense, not a requirement

Actually “fair use” is defined by law in a lot of counties. It’s not a defence, it’s a legal right.

> You don't need permission to claim fair use;

That’s not what I said.

> it's a legal defense if you're sued Seeking permission can backfire

It’s spelt “defence” (with a C not an S) and the point is you seek permission before distribution, not after

Not everything in life follows the “ask for forgiveness not permission” rule ;)

> Copyright holders may deny permission even when fair use would apply, creating unnecessary barriers.

Copyright holders cannot deny fair use in jurisdictions where fair use laws apply.

The difference between Seek and Ask Forgiveness in the situation outlined is that Seek lays out costs before hand and generally they are minimal, and Ask Forgiveness can determine costs at the will of the person sampled or remove the work completely from circulation.