Copyright Aid

Me and a team of designers and developers have built a online store which sells funny t-shirt that has some faces on it that are widely used on the internet but own no copyright or trademarks.

Is there anyway we can copyright them OR copyright the t-shirts with them on?

Thanks.

So, I'm building a guitar effects pedal. It's based of the schematic of a certain pedal except I've added, taken away and changed a lot of components and values to get a different sound from it.

Would it break copyright laws if I sold it?

Awesome.

So as long as it doesn't say "Darth Vader" or have text like that it is fine to use?

Luckily it doesn't have any text and isn't copied.

Thanks a lot.

So, I've drawn and made a darth vader cartoon style t-shirt that I hope to sell to a small circle of people.

Is this again copyright law?