> Though my understanding so far is that this works for trademarks because it only restricts the use of symbols as part of a brand, not their everyday use or use in other commercial activities - in contrast to copyright or patents.
Not exactly.
In some of the cases identified in this article the color itself is trademarked.
Trademarks only apply for specific categories though. For example you cannot use the Tiffany Blue for anything in international class 014:
> Precious metals and their alloys and goods in precious metals or coated therewith, not included in other classes; jewellery, precious stones; horological and chronometric instruments. - Precious metals and their alloys and goods in precious metals or coated therewith, not included in other classes; jewellery, precious stones; horological and chronometric instruments.
But that completely restricts the use of that color in that class. You don't have to use any other branding elements from Tiffany to be infringing.
> it wouldn't restrict anyone from taking pictures of the sky.
Trademarks cannot restrict taking pictures.
Generally speaking trademarks only restrict commercial usage - however "publication" can be considered commercial use and "publication" can cover a very large set of things.
For example if you took a photo of the Tiffany blue and some jewellery and then shared it on Facebook it's likely Tiffany could succeed in a takedown request.
> For example if you took a photo of the Tiffany blue and some jewellery and then shared it on Facebook it's likely Tiffany could succeed in a takedown request.
If the mark on the jewelry is genuine (i.e., if you are reselling genuine Tiffany jewelry), then Tiffany should not succeed in a takedown request because of the trademark exhaustion doctrine (an analogue of first-sale doctrine for copyright). On the other hand, appropriating the Tiffany marks to sell non-Tiffany jewelry would probably be infringing.
(Edit: It's even more complicated. Even if you weren't selling jewelry, you could still be passing off your use as if it were authorized by Tiffany (e.g., in an advertisement for something else). If, however, you were parodying Tiffany in your photo, then your use of the marks could be trademark fair use. So there are many ways a photo of jewelry accompanied by the Tiffany marks could go.)
To clarify - I meant if you took a photo of a Tiffany blue color swatch and then posted a pic of it next to non-Tiffany jewellery a takedown request could succeed.
Not exactly.
In some of the cases identified in this article the color itself is trademarked.
Trademarks only apply for specific categories though. For example you cannot use the Tiffany Blue for anything in international class 014:
> Precious metals and their alloys and goods in precious metals or coated therewith, not included in other classes; jewellery, precious stones; horological and chronometric instruments. - Precious metals and their alloys and goods in precious metals or coated therewith, not included in other classes; jewellery, precious stones; horological and chronometric instruments.
But that completely restricts the use of that color in that class. You don't have to use any other branding elements from Tiffany to be infringing.
> it wouldn't restrict anyone from taking pictures of the sky.
Trademarks cannot restrict taking pictures.
Generally speaking trademarks only restrict commercial usage - however "publication" can be considered commercial use and "publication" can cover a very large set of things.
For example if you took a photo of the Tiffany blue and some jewellery and then shared it on Facebook it's likely Tiffany could succeed in a takedown request.
[1] https://trademarks.justia.com/865/71/tiffany-86571740.html