Tikalon Header Blog Logo

Morse Code and Software Patents

June 29, 2015

The world is a better place because of patents. Patents have the inconvenient aspect that they prevent the free practice of an invention by anyone except the inventor and his licensees for a period of time. However, that aspect acts as an incentive for invention, and the inventor must disclose his invention in the published patent document in a manner that allows it to be reproduced by anyone "skilled in the art." That way, the invention can be practiced in the public domain when the term of the patent expires.

Quite a few people are thankful for this aspect of patenting, since they can eventually buy much less expensive generic versions of drugs after the drug patents expire. If you wait long enough, a version of that electronic device you could never afford will be found in the bargain bin of your local big box store. That's because most of the myriad technology patents that enable it have expired to the benefit of advancing technology.

One of my first electronic calculators, an HP-33C Scientific Programmable Calculator, cost about a hundred dollars when I bought it in 1980 ($300 in today's money). An equivalent calculator can now be purchased for less than ten dollars, and that calculator might derive its power from photovoltaic cells which were too inefficient and too expensive in 1980.

An HP-33C Scientific Programmable Calculator

My HP-33C Scientific Programmable Calculator, no longer working, but retained as a keepsake.

This calculator had a display with an eight digit mantissa and two digit exponent formed from red light-emitting diodes.

It used Reverse Polish notation, which was easy for someone accustomed to using stacks in assembly language and Forth.

(Photo by author.)

Not everything is patentable.[1] Einstein's famous E = mc2 equation is a great discovery, but it's not an invention. mathematical algorithms, natural phenomena, and laws of nature are not patentable. As the United States Patent and Trademark Office states in its Manual of Patent Examining Procedure,
"A principle, in the abstract, is a fundamental truth; an original cause; a motive; these cannot be patented, as no one can claim in either of them an exclusive right... manifestations of laws of nature are part of the storehouse of knowledge, free to all men and reserved exclusively to none."[1]
One very important aspect of patentability is that "a new mineral discovered in the earth or a new plant found in the wild is not patentable subject matter." I'm not a patent attorney, but it's not too much of a stretch to predict that any plants or minerals found on another planet can't be patented, so dilithium crystals are in the public domain. However, a process for creation of dilithium crystals that would preclude needing to mine them would be patentable. "New compositions of matter," are patentable.

If you statistically examine how often the individual letters are used in the English language, you'll see that some letters are used much more often than others (see figure). This fact was important to breaking secret codes about a hundred years ago, before electromechanical and computer cryptanalysis became common. This letter frequency relationship, which resembles a natural law, became important to telegraphy. I wrote about telegraphy in a previous article (The Telegraph, July 25, 2011).

Letter frequency in the English language

Approximate letter frequency in the English language. (Graphed by the author using Gnumeric.)

On January 11, 1838, Samuel F.B. Morse and Alfred Vail demonstrated a telegraph system with a two mile range at the Speedwell Ironworks in Morristown, New Jersey. This was a simple, single wire circuit, that used Earth's conductance as a return path ("ground"). Morse was a portrait painter who was not especially skilled with electricity, so it's thought that Vail's family money and technical skill were important parts of the venture.

Although the telegraph code is called "Morse Code," it appears that Vail deserves most of the credit. Vail derived a letter frequency graph similar to that shown in the figure by an analysis of the movable type in type cases at the local newspaper. He translated his findings into an efficient use of "dots" and "dashes" for telegraph transmission. Since the letter e is the most common, it was represented by the shortest code, a single "dot." The next most common character, t, is represented by a single "dash," in the modern version of the code, but not in Vail's original scheme (see figure).

Telegraphy code in the original Morse patent (1840)

(Telegraphy code as shown on the first page of the original Morse patent (1840). Although the letter, e is a single dot in both this code and today's international Morse code, most of the other characters are different. Via Google Patents.)[2)]

The fundamental Morse telegraph patent, issued in 1840, is most important because it demonstrates the idea of a repeater.[2] The repeater circuit, implemented as cascaded electromagnetic relays, was a way to circumvent the inherent resistive loss of telegraph wires and allow transmission of a telegraph signal over great distances. The patent also included a very broad claim, claim 8, allowed by the patent examiner, but subsequently disallowed by the US Supreme Court,
"The combination and arrangement of electro-magnets in one or more circuits of metallic conductors with armatures of magnets for transmitting intelligence by signs and sounds, or either, between distant points and to different points simultaneously."[2]

This essentially claims all transmission of
information over distances using wires and electromagnetism. In 1853, the US Supreme Court in the case of O'Reilly v. Morse ruled that Morse had invented a practical telegraph, but he didn't have ownership of all possible telegraphs. The idea in claim 8 was a "principle," and it was not a mechanism that could be protected by a patent. The patent was reissued without the claim.[3]

This ruling confirmed that it's not possible to patent an abstract idea. You can patent just its implementation. Although this ruling happened more than a hundred and fifty years ago, it continues to be cited today in cases involving
software patents.

A Morse repeater

The electromagnetic relay repeater circuit of the Morse 1840 patent, rendered using modern notation. (Illustration by the author using Inkscape.)

In my estimation, one of the more famous software patents is that of the lossless data compression method called Lempel–Ziv–Welch (LZW).[4] LZW can compress an English text file by about 50%, which was a huge advantage in the early days of limited computer memory and low data rate transmission channels. It was an important part of the early Internet, since it's used in the GIF image format, available since 1987.


  1. United States Patent and Trademark Office, "Patent Subject Matter Eligibility," Manual of Patent Examining Procedure, Chapter 2100, Section 2106.
  2. Samuel F. B. Morse, "Improvement in the mode of communicating information by signals by the application of electromagnetism," U.S. Patent No. 1,647 (June 20, 1840).
  3. S. F. B. Morse, "Improvement in electro-magnetic telegraphs," U.S. Reissue Patent RE117 (June 13, 1848).
  4. Terry A. Welch, "High speed data compression and decompression apparatus and method," U.S. Patent No. 4,558,302 (December 10, 1985)

Permanent Link to this article

Linked Keywords: Patent; invention; inventor; license; licensee; patent application; reproducibility; reproduced; public domain; generic drug; prescription drug; electronics; electronic device; bargain bin; big box store; technology; electronic calculator; HP-33C Scientific Programmable Calculator; dollar; solar cell; photovoltaic cell; energy conversion efficiency; inefficient; souvenir; keepsake; significand; mantissa; floating point; exponent; light-emitting diode; Reverse Polish notation; stack; assembly language; Forth programming language; Albert Einstein; mass-energy equivalence; E = mc2; discovery; mathematical; algorithm; natural phenomena; physical law; laws of nature; United States Patent and Trademark Office; Manual of Patent Examining Procedure; mineral; lithosphere; earth; plant; wilderness; wild; patent attorney; extrapolation; stretch; prediction; predict; planet; dilithium crystal; chemical process; mining; mine; statistics; statistical; alphabet letter; English language; letter frequencies; breaking secret codes; Bombe; electromechanical; computer; cryptanalysis; telegraphy; Gnumeric; Samuel F.B. Morse; Alfred Vail; electrical telegraph; mile; Speedwell Ironworks; Morristown, New Jersey; wire; circuit; Earth's conductance; ground; portrait painting; portrait painter; electricity; inheritance; family money; technician; technical skill; venture; telegraph code; Morse Code; analysis; movable type; type case; newspaper; telegraphy code; international Morse code; Google Patents; repeater; electromagnet; electromagnetic; relay; resistive loss; patent claim; patent examiner; Supreme Court of the United States; information; electromagnetism; O'Reilly v. Morse; software patent; electronic symbol notation; Inkscape; lossless data compression; Lempel–Ziv–Welch; computer memory; bit rate; data rate; Internet; GIF image format; Samuel F. B. Morse, "Improvement in the mode of communicating information by signals by the application of electromagnetism," U.S. Patent No. 1,647 (June 20, 1840); S. F. B. Morse, "Improvement in electro-magnetic telegraphs," U.S. Reissue Patent RE117 (June 13, 1848); Terry A. Welch, "High speed data compression and decompression apparatus and method," U.S. Patent No. 4,558,302 (December 10, 1985).