How Is a Logo or Trademark Different from a Coat of Arms?

Frankly, an honest answer to the question posed above is, "Sometimes, not very much."

But let's start with defining some terms.

The term trademark refers to a recognizable insignia [e.g., a logo], phrase, word, or symbol that denotes a specific product and legally differentiates it from all other products of its kind. A trademark exclusively identifies a product as belonging to a specific company and recognizes the company's ownership of the brand. Trademarks can be registered, giving legal protections to the owner.

To register a trademarked logo, among other things, the owner will need to describe:

"The product(s) or service(s) the logo will represent, along the class of goods or services for which you’re registering the trademark"; and

"A .jpg image file of the final version of the logo or design. If your logo is in color, you also need a description of the colors and where they’re used."

This last part is important. Here, for example, is a well-known registered trademark:

The red color is specifically designated as "Pantone 484".

Were it some other color than Pantone 484 red, it technically would not be the registered trademark of the Coca-Cola Corporation of Atlanta, Georgia. For example:

That said, I wouldn't recommend changing the color of the Coke logo and use it as your own, whether for a brand of cola or any other purpose.

Still, my point here is that, unlike heraldry, where "azure" can be any one of a wide variety of shades of blue, "gules" can be any one of a wide variety of shades of red, and so on, trademarks (and logos) are far more restrictive.

The same is true of the shapes and letters on a trademark or logo. The font is specified; the shapes are described in detail, and cannot be altered. (Well, not without registering a new trademark with the new specifications, anyway.)

Here, again, heraldry gives us a wider range of options.

Take a blazon from the English College of Arms in 1694, for example: Vert a Colledge, or Edifice Mason'd Argent in Chief a Sun rising Or the Hemisphere proper.

These are the arms granted to the College of William and Mary in Williamsburg, Virginia. They appear on a seal used by the College from 1694 to 1783.

So what does a "Colledge, or Edifice" look like? Frankly, it looks like whatever the thinks it looks like.

And, indeed, a number of variants are noted by the College itself:

Buildings, full sun with human face, rays, feathery scrolled border with foliage, leaves crossed on field. Drawing from ___ Example in "Coat of Arms," University Archives Subject File Collection.

Buildings, full sun with human face, rays, scrolled border with foliage, flower on the left as observed, leaves crossed on field. Designed for the Frenchman's Map from Eric M. Simon of ____ of Pittsfield, MA.

Buildings, full sun with human face, rays, scrolled border, Latin inscription "Sig. Collegii R. et R. Gulielmi et Mariae in Virginia. Used by the Registrar's Office in 1947.

Buildings, full sun with human face, rays, drapery held with sconces, foliage, no text. Examples: College buildings including Tucker Hall, Blair Hall, Wildflower Refuge (no drapery).

Nonetheless, however, the College of William and Mary approached the College of Arms in London in the 1920s in an attempt to obtain a definitive example of what their arms look like. They received this:

(Please note the differences as well as the similarities of this depiction and the seal used above.)

Despite the freedom given in heraldry which allows for a wide range of potential depictions of a charge, the College of William and Mary has treated this example from the College of Arms as definitive, and has essentially turned it from a coat of arms into a logo/trademark.

Here are some examples of this:

And so, with these examples, we repeat our answer to the question posed in the title of this post: How is a logo or trademark different from a coat of arms?

"Sometimes, not very much."

Especially when a single depiction of a coat of arms is treated as if it is the only model to be emulated in all future depictions. That's not heraldry; that's a trademark.