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Shape Making:

Thangles and the Blank Form Rule

Quilting is all about shapes.  And there are many, many, many tools and strategies for achieving great shapes.  


Today's topic:  Thangles 


Half-square triangles are commonly used in quilting.   And there are many techniques.


One technique are Thangles.  These are sets of paper that you buy, and then you place them over fabric (two piece strip) and you have guidance in making the triangles.  


Thangles come in all sizes.  They aren't that expensive.  They are helpful.  Here's a really great site that explains how to use Thangles.


But what about the copyright status of Thangles?


We see on Thangles that there is a copyright notice on each strip.  What does that mean exactly?  Can you not make copies of them? Does copyright cover the method of making the half-square triangles?  


The method of making half-square triangles that is created by Thangles is not covered by copyright.  This is because of the concept of the "blank forms rule."

There are lots of Thangles at Amazon and local quilt shops.  We are not getting paid by Thangles. Just put a link to make it more convenient to search.


Copyright Concept: Blank Forms Rule


An account invented a method of bookkeeping, and he wrote a book about it, which included forms for the accounting method.  Then, someone else wnated to make forms to use for that book.  Baker v. Seldon 101 U.S. 99 (1879).  This was a big case.  It gave us two concepts, one of which is the blank forms rule.  Could someone else copy Selden's system, and make forms of their own?  The U.S. Supreme Court said Yes!  


1.  Patents versus Copyright

First, copyright does not protect "systems" or "inventions."  That's why patents are for.  

2.  Idea/Expression Dichotomy

Second, ideas are not protected by copyright (the idea to paint clouds, for example).  Only the expression is protected (an acutal painting of clouds).  In the case of Selden's bookkeeping system, the ideas were not protected, but only how he wrote about those ideas.  He wrote 650 words describing the system -- that expression -- how he described the system was protected by copyright.

3.  Merger Doctrine

But what if how he described it was the only way to describe it?  (Think of a shampoo bottle that says, "Apply. Rinse. Repeat."  The court reasoned that if the expression merges with the best and only way to describe something, it is not protected by copyright. 

4.  Blank forms rule

 by copyright law.  Checks, basic accounting forms, and other non-creative forms are not protected.  The design on a check (a duck, for instance) might be protected, but the basics of a check is not protected. And here is where Baker v. Seldon applies to Thangles.  The form to use the accounting system is not protected.  


Here's the current copyright law:  Section 102(b):


In no case does copyright protection for an original work of authorship extend to any idea, procedure, process, system, method of operation, concept, principle, or discovery, regardless of the form in which it is described, explained, illustrated, or embodied in such work.


Here's further clarification: 

§202.1   Material not subject to copyright.

The following are examples of works not subject to copyright and applications for registration of such works cannot be entertained:

(a) Words and short phrases such as names, titles, and slogans; familiar symbols or designs; mere variations of typographic ornamentation, lettering or coloring; mere listing of ingredients or contents;

(b) Ideas, plans, methods, systems, or devices, as distinguished from the particular manner in which they are expressed or described in a writing;

(c) Blank forms, such as time cards, graph paper, account books, diaries, bank checks, scorecards, address books, report forms, order forms and the like, which are designed for recording information and do not in themselves convey information;

(d) Works consisting entirely of information that is common property containing no original authorship, such as, for example: Standard calendars, height and weight charts, tape measures and rulers, schedules of sporting events, and lists or tables taken from public documents or other common sources.

(e) Typeface as typeface.

[24 FR 4956, June 18, 1959, as amended at 38 FR 3045, Feb. 1, 1973; 57 FR 6202, Feb. 21, 1992


So the question is, are Thangles copyrightable, or do they fall under the blank forms rule?

Yes, the selection, arrangement, and coordination of the elements, but not the functional elements.



  1. The Thangle system is not copyrightable.  

  2. The Thangle strips also fall under the blank forms rule.

  3. There is no registration of Thangles at the U.S. Copyright Office. 

  4. There is a copyright notice on the bottom of each Thangle.   What would be protected by this copyright is the expression of the system, and not the system itself.  So, the selection, arrangement, and coordination of the elements (e.g. where "Thanges" name appears and the font used.)


What does this mean? 

  • It is not illegal to make your own version of the method used in Thangles.  While there may be a thin copyright, it is not for the method or system that is created.

  • But it is much more convenient to purchase Thangles.

  • And they advertise that they use a special ink so that when you iron the ink does not get on the fabric or the iron.



And what about the Thangle business?  

"Thangles," the term has a "TM" next to it!  What does that mean?  No one else may call their product "Thangles" for the use.  Thangles is a strong mark, a made up word.   The company's brand and goodwill carry more weight than does the copyright on the Thangle itself.  You buy Thangles because you know that they will work, that they are great to use, etc.  The brand keeps you buying more.  The special paper, the ease of use -- this is part of the brand.  



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