The question of ownership of Amiga-related intellectual property post-Commodore is famously difficult to answer. My question is: does anyone "own" Commodore's semiconductor IP now, and if so, who?

I imagine that patents have expired everywhere that they were granted, as it's been 26 years since Commodore went bankrupt. I would also guess (but welcome confirmation) that the various Amiga chip designs are part of the IP that Escom->Amiga Inc.->A-Eon own/claim to own.

But Commodore had a lot of other semiconductor designs too, including those gained through the MOS acquisition: who owns those now?

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    Advertise that you have a soft vhdl version of amiga for sale and see who sues you :-)
    – pm100
    Commented Aug 12, 2020 at 13:53
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    @pm100 one of the motivations for my question is that I have a Vampire board: an FPGA reimplementation of (among other things) the AGA chipset.
    – Graham Lee
    Commented Aug 12, 2020 at 15:02

1 Answer 1


TL;DR The ownership issue is really associated with the trademarked brand and product names, and the copyrighted ROM software, not the processor/co-processor hardware.

I think there are two mainstream products who's licensing terms are instructive to understanding how the earlier (non-Amiga) Commodore IP has been used and defended by the new rights holders after Commodore's liquidation in 1994.

  1. The 2004 C64 Direct-to-TV - a single-chip implementation of the Commodore 64 computer, contained in a joystick. Also known as the "C64 DTV".

  2. The 2019 THEC64 mini/maxi - A software emulator based recreation of the C64 with reproduction case.

The C64 DTV, which was sold by Mammoth Games, has licensing terms printed on the bottom of the device stating "C64 and Commodore 64 are registered trademarks of Commodore International B.V., used under license". Tulip Computers owned the rights to the C64 (acquired in 1997) and authorized this product to be built. Later, in late-2004, Tulip sold the Commodore trademark to a new holder, and apparently conveyed licensing that allowed continued sale and use of the trademark by the C64 DTV.

Since the time of the C64 DTV, there have been many re-implementations of the C64 hardware offered for sale, usually implemented as compatible VHDL synthesized in an FPGA. Though some newer products like THEC64 rely on modern SoC computers with software emulation of the C64 hardware.

To my knowledge, such reverse-engineering of hardware via either FPGA's or emulation doesn't require a license, and none of these products have resulted in successful law suits. However, there are copyright holder issues related to the C64 ROM software and to the use of the trademarks "Commodore" and "Commodore 64".

Thus, we can see this in practice by just looking at the rights acknowledgements that come with THEC64. This states "CBM 8-Bit ROMs © 1977-1984 Cloanto® Corporation. All Rights Reserved. Furnished under license from Cloanto®". Notably, the trademarked terms that could be licensed for this product are avoided. Instead, the new trademark "THEC64" has been registered by the manufacturer to use in the marketing of this product. Meanwhile, they had to go to Cloanto for rights to use their copyrighted ROM.

Obviously, both of these products rely on previous Commodore IP related to the C64, including the C64's custom chips, CPU, and ROM's. Additionally, and probably more important, the C64 DTV gleefully used the Commodore brand and C64 name/trademark when sold to the public in 2004. In contrast, THEC64 actively avoids trademarked terms that still have ownership claims associated with them. The timeline of ownership for both trademarks and patents is well-documented on Wikipedia's Commodore International page. Gateway 2000, the large American computer manufacturer, ended up with the Commodore IP in 1997, but was mainly interested in the Amiga patents. Thus, Gateway sold off the trademarks and copyrights, and presumably kept and enforced the patents until they expired. This leaves us with the prevailing situation today, centered around trademarks and ROM copyrights.

In conclusion, Commodore's old IP is only protected by the new rights-holders through trademark licensing and copyrights on the software ROM. The other silicon, like Amiga custom chips, if not still covered by a patent, can be and has been reverse-engineered and sold by various manufacturers.

So, the situation does not appear to be any different whether you are talking about the earlier Commodore 8-bit computers, or the later Amigas. Such products would require licensed ROM's, being either the C64 firmware or Amiga Kickstart, both of which are owned by Cloanto. If you want to use trademarked terms like "Commodore" or "Amiga" on a product, then that is also likely to require a license.

*** I am not a lawyer, and nothing in this answer should be construed as legal advice. This is my opinion based on a sampling of existing products and their published license arrangements.

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    How much of the semiconductor IP would have any recognized copyright protection? When Ricoh made the processor used in the Famicom/NES, they rather famously photographed Commodore's 6502, identified the parts covered by patent, and duplicated everything else verbatim on the basis that semiconductor layouts were not regarded as copyrightable works. I know the laws were changed after that, and would guess some of the chips produced late in the Amiga's life would be covered by the new laws, but I don't know any specifics.
    – supercat
    Commented Aug 12, 2020 at 16:37
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    @supercat Good point. I'm not aware of anyone actually trying to manufacture Amiga custom "clone" chips from die shots. It feels like that would be cost-prohibitive at low volumes, anyway.
    – Brian H
    Commented Aug 12, 2020 at 16:49
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    Although nobody's making direct photographic clones from die shots, I don't think it's clear when designs derived from the die shots would or would not be "derivative works".
    – supercat
    Commented Aug 12, 2020 at 17:33
  • I think you're probably right that the only remaining protection is trademark protection, though I was also interested in @supercat's notion of reverse-engineered designs (whether from die shots or otherwise). Not necessarily copyright, though that's a good thought. There's also the "trade secret" IP nuclear option; someone could (laughably) claim that the 6502's internal design is a trade secret they acquired from C= and cloning it harms their market position.
    – Graham Lee
    Commented Aug 13, 2020 at 15:27
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    @GrahamLee: Once a company's assets have been liquidated, I would think any kind of trade-secret case would become untenable. If one buys a bunch of filing cabinets at liquidation, without any advance agreement as to the disposition of the contents, such a sale would represent a disclosure of all information therein. It wouldn't waive copyright, patents, or trademarks on such contents (though IMHO copyright law should recognize a means by which such content could be adjudicated as abandoned), but sale of cabinets containing information does not show intent to keep it secret.
    – supercat
    Commented Aug 13, 2020 at 15:43

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