Accidents happen, and more often than we realize, they lead to remarkable breakthroughs. From labs to kitchens, the history of innovation is filled with chance discoveries that transformed industries and changed lives. This article explores some of the most famous inventions that emerged from unexpected twists of fate, reminding us all of the power of curiosity and open-minded thinking.
The Legal Confusion
Let’s look at whether accidental discoveries are patentable. In the US, “Whoever invents or discovers any new and useful process, machine, manufacture, or composition of matter, or any new and useful improvement thereof, may obtain a patent therefor”. [35 U.S.C. § 101]. “Patentability shall not be negated by the manner in which the invention was made.” [35 U.S.C. § 103]. Seems pretty straightforward: You can invent and patent something, or you can discover and patent something. Think of it as the difference between inventing a drug and discovering a way to measure drug levels in the body to maximize efficacy.
Oh, wait. Now it isn’t so straightforward because the U.S. Supreme Court has effectively deleted the parts of the statute that allow patenting of discoveries. In Mayo v. Prometheus, the Supreme Court leads with “an important implicit exception” to patentability: Natural phenomena and abstract ideas are not patentable. Abstract ideas are looked at in depth in Alice v. CLS Bank. But nearly everything you can discover (rather than invent) will be a natural phenomena. Consider antibiotics – a company might spend a billion dollars finding and testing naturally occurring chemicals for efficacy against bacteria only to find that they can’t get a patent to protect the fruits of that enormous investment. The result? Nobody will make that kind of investment. Even discovering a diagnostic test that can eliminate the need for amniocentesis and the 1% miscarriage risk it carries, while an “an important discovery and a valuable contribution to the medical field” was held not patentable because it searched for something naturally occurring (but not previously discovered).
The Erection Revelation: Birth of Sildenafil (Viagra)
In the early 1990s, researchers at Pfizer were diligently developing a new medication intended to treat hypertension and angina. The compound they worked on—sildenafil—showed potential in helping blood vessels relax, but clinical trials failed to demonstrate the hoped-for improvement in heart conditions. Disappointed by these lackluster results, scientists prepared to pivot or abandon the project entirely.
Then a surprising report began to emerge. Male trial participants noted a distinctly unintended benefit: stronger and more sustained erections. This observation was too significant to ignore. After reexamining the drug’s mechanism, Pfizer swiftly recognized the enormous potential for addressing erectile dysfunction. Released under the brand name Viagra in 1998, it became a game-changing blockbuster medication, redefining both the pharmaceutical market and the cultural conversation around men’s sexual health. What began as a failed effort to treat angina ended up rewriting the rules of ED treatment and paving the way for a new class of related drugs.
Post-it® Notes: A “Weak” Glue That Stuck Around
Chemists at 3M spend their days dreaming up all sorts of new adhesives, but in 1968, Spencer Silver discovered something he was sure no one wanted: a glue that wasn’t very sticky. It clung lightly to surfaces without bonding firmly and could be peeled away without leaving any residue. Despite his enthusiasm, no one at 3M knew what to do with it, and the innovation sat without a clear application.
It would be another employee, Arthur Fry, who gave the low-tack adhesive new life. Fry, seeking a way to keep bookmarks from slipping out of his church choir’s hymnbooks, realized that Silver’s “failed” glue would be perfect: it would stay in place yet lift off without damaging the pages. By 1980, 3M launched the iconic Post-it® Notes. Those small, canary-yellow squares quickly became a worldwide phenomenon, proving that a seemingly useless invention could become an office essential through a spark of lateral thinking.
A Melted Candy Bar and the Microwave Oven
During the 1940s, engineer Percy Spencer was working at Raytheon on the technology behind radar magnetrons. One day, he noticed the chocolate bar in his pocket had melted while he stood near an active magnetron. Far from being annoyed, Spencer was intrigued. He tested popcorn kernels next, and they popped readily under microwave exposure. Encouraged by these results, he tried an egg—which, with slightly more dramatic effect, exploded.
These curiosities soon led Raytheon to develop the first commercial microwave oven, called the Radarange. Early models were bulky, expensive, and better suited to restaurants and factories. Over time, the machines were streamlined and made increasingly affordable, becoming a staple in home kitchens worldwide. An errant candy bar melting in a pocket was enough to spark an idea that saved families untold hours of cooking time.
Teflon™: A Slippery Accident Turned Household Staple
In 1938, chemist Roy J. Plunkett at DuPont was investigating new refrigerants when a seemingly faulty canister wouldn’t release its gas. Upon examining the interior, he found a peculiar, waxy substance that was incredibly slippery and chemically unreactive. This material, polytetrafluoroethylene (PTFE), possessed properties unlike anything the lab had ever seen.
Branded as Teflon™, PTFE entered the commercial market a few years later. Not only did it herald the era of non-stick cookware—making it easier for home cooks to fry eggs and pancakes without leaving half of breakfast clinging to the pan—but it also became a fixture of various industrial and medical applications. Teflon™ coated everything from machine parts to medical implants, demonstrating that an accidental byproduct can expand beyond a single product line to revolutionize multiple industries.
Penicillin: The Moldy Dish That Saved Millions
No discussion of accidental inventions is complete without mentioning penicillin. In 1928, Scottish bacteriologist Alexander Fleming returned to his messy lab at St. Mary’s Hospital after a brief vacation. Expecting a routine clean-up, he instead noticed that a Petri dish containing Staphylococcus bacteria had grown mold (later identified as Penicillium notatum). Where the mold flourished, the bacteria around it had died.
Recognizing the medical potential of this chance observation, Fleming began further experiments. Yet it wasn’t until Howard Florey and Ernst Chain refined penicillin for mass production during World War II that the antibiotic truly transformed modern medicine. What started as an unintentional culture contamination grew into one of humanity’s greatest medicinal discoveries, saving countless lives and ushering in the age of antibiotics. Of course, as I discussed above, it would almost certainly not be patentable under Mayo and Ariosa.
Velcro®: Nature’s Unexpected Gift
Nature has long inspired human innovation, but few examples are more direct than Velcro®. Swiss engineer George de Mestral experienced an “aha” moment in 1941 when he examined the cockleburs that clung to his dog’s fur after a hunting trip. Under a microscope, he noticed the burrs had tiny hooks that latched onto fabric and hair.
Intrigued, de Mestral spent years perfecting a synthetic version of this hook-and-loop mechanism, ultimately patenting it in 1955. He named his invention Velcro®, combining the words “velour” and “crochet.” Although it wasn’t an immediate commercial smash, Velcro® gradually became indispensable for fastening sneakers, securing gear, and even assisting astronauts during NASA missions. The humble cocklebur’s design turned out to be a key to a whole world of products that click or zip together with ease.
Surprising Twists: LSD, Bubble Wrap, Saccharin, and Play-Doh
Not all accidents stay within the usual boundaries of adhesives or medicines. LSD arose in the 1930s when chemist Albert Hofmann was searching for circulatory stimulants. An unintentional dose led to vivid hallucinations, reshaping psychiatric research and, eventually, an entire counterculture movement—before legal restrictions curtailed its broader use.
Other everyday products also claim serendipitous origins. Bubble Wrap was initially pitched as a funky new type of wallpaper. When that idea failed to catch on, its creators pivoted toward packaging—an application that proved so successful, it’s hard to ship a parcel today without encountering it. Saccharin came about in 1879 when Constantin Fahlberg forgot to wash his hands after working with coal tar derivatives and noticed a surprisingly sweet taste on his dinner roll. Even Play-Doh started out as a wallpaper cleaner before it was rebranded as a children’s modeling compound. Each story highlights the importance of asking, “What else could this be?” rather than simply discarding a failed experiment.
The Hidden Value of Accidents
Serendipity and straight up good luck play a powerful role in invention. Researchers often find themselves frustrated by unexpected results, but it’s precisely in those unpredicted moments that breakthroughs can emerge. Many of these discoveries required keen observers who recognized their importance—and the vision to see how they might be repurposed for entirely new markets. Historians frequently point to these stories as examples of science in action, where experiments go awry in ways that lead to leaps forward rather than dead ends.
Whether you’re marveling at a melted candy bar that inspired the microwave or popping a little pill that was supposed to help the heart but ended up assisting something else entirely, the world of accidental inventions has a lot to teach us. It demonstrates that discovery often requires a dash of curiosity, a willingness to explore the unexpected, and enough humility to realize that what looks like a mistake might just be your ticket to the next big thing.
Importantly, Congress needs to take the reigns here. If antibiotics that occur naturally aren’t patentable on discovery, if diagnostic tests are almost categorically ineligible, the financial incentive to invest billions in figuring out how to turn these natural compounds into something useful will disappear. I recommend you visit US Inventor for more information.