Patent Experimental Use – Invalidity in Lough V Brunswick (Fed Cir 1997)


Imagine that you are a car mechanic. You notice that engine coolant frequently corrodes a part of the motors. As a mechanic, you have to replace this part once a year. To address this problem, you design a new part to contain the coolant. Hopefully, the part you made will last longer.

To find out if the part works, you decide to test your invention. You install the part into your friends’ cars, explaining to them that you want to see if the part will help keep the motor from corroding. Your friends use their cars for two years, with no problems. Therefore, your invention outperforms existing products. You decide to patent your invention.

Some time later, a car maker begins selling a new car motor with a device like your part installed in the car. Believing that the company illegally used your patented invention, you sue to enforce your patent. However, before you have a chance to present evidence, the car manufacturer asks the court to dismiss your lawsuit. In a motion for summary judgment, the car maker argues that a trial is not necessary because the car maker has not violated the Patent Code, even if everything you say is correct. The car maker claims that you gave up your patent rights because, contrary to patent law, you spent more than a year testing your invention in public. In other words, the car maker argues that the Patent and Trademark Office should never have given you a patent.

However, you believe that you needed the two years to test your invention to ensure that your device would work as you intended. You tell the judge that a jury should decide whether a long period of testing prevents patenting an invention. You argue that whether you spent too long testing the device in public, making your patent invalid, is not a question that a judge can decide without hearing evidence on the issue.

However, the judge agrees with the car maker that this is a question of law. This ruling means that a judge decides the question without hearing evidence. Despite your objection, the judge grants the car manufacturer’s motion for a summary judgment. This means that you did not get a chance to have a jury trial because the judge ruled on a question of law without hearing your evidence.

This scenario could happen in real life. Just like the hypothetical court, the Federal Circuit Court of Appeals in Lough v. Brunswick Corp., considered whether an inventor’s testing of an invention was a question of fact or a question of law. The Lough court held that determining an invention’s use in testing is a question of law. The Lough court’s decision has failed to remove confusion on the time limit to apply for a patent. Fortunately, the United States Supreme Court will soon consider the Patent Code’s time limit for patent filing in Pfaff v. Wells Electronics. Hopefully, the Supreme Court will settle this area of patent law.

This Note will show some of the Lough court’s errors that created the current confusion on the time limit for patent filing. The Note begins by explaining the United States patent system, including bars to an inventor’s use of an invention before filing for a patent. Part II reviews the Supreme Court’s holding in Kendall v. Winsor that these bars on the use of an invention before patenting are questions of fact. Part III shows how the Federal Circuit overlooked this Supreme Court precedent. Part IV then describes Lough v. Brunswick Corp.’s facts, procedure, holding, and reasoning. Part V analyzes the Federal Circuit’s Lough decision. Specifically, Part V argues that the Federal Circuit departed from Supreme Court case law when the court held that bars on the use of an invention before patenting are questions of law. Also, the Federal Circuit committed a sequence of errors leading up to Lough. This Note concludes that the Federal Circuit Court misinterpreted the case law and states that whether an inventor tested the invention should be a question of fact.


A. General Patent Law

Under certain conditions, the Patent Code grants inventors exclusive rights to their inventions. If an inventor obtains a patent, the Patent Code gives an inventor monopoly rights for twenty years after applying for a patent. During this time, the patentee has the sole right to make, sell, import, or use the invention in the United States.

To avoid unfairly prolonging these monopoly rights, an inventor has only a limited time to apply for a patent to protect an invention. The reference point for this time limit is the date on which the inventor applied for a patent. The patent system creates a one-year grace period during which the inventor may use the invention before applying for a patent.

B. Public Use

If the inventor uses the invention in public more than a year before applying for a patent, an inventor loses the right to obtain a patent. If the inventor does not apply for a patent within one year after using the invention in public, the law assumes that the inventor did not want patent protection and that the inventor donated the invention to the public. As a result, the inventor is unable to obtain a patent after a year of use in public.

“Public use” of an invention occurs when anyone uses the invention in its natural and intended manner. The public use of an invention need not be publicly accessible. For example, if an airline’s domestic commercial flight has an inventor’s unpatented navigation device installed on the plane, the device is in public use. The public use doctrine is codified in 102(b) of the Patent Code. Section 102(b) of the Patent Code bars an inventor from obtaining a patent if any public use of a completed invention occurs more than one year before the inventor applies for a patent.

C. Experimental Use

Courts extend the one-year time limit if the inventor tests the invention. Section 102(b) does not explicitly consider an inventor’s need to test an invention. Instead, “experimental use” is a judicially-created doctrine intended to give an inventor extra time to refine an invention. During this time, an inventor may conduct experiments in public without losing Patent Code protections. Patent law determines that experimental use occurs when the inventor, or anyone else, tests an invention in such a manner. Experimental use of an invention may negate a 102(b) claim that a patent is invalid. This gives an inventor one year of public use, plus any reasonable period of experimental use, before 102(b) bars the inventor from obtaining a patent.


When deciding public use and experimental use questions, the Supreme Court has uniformly treated 102(b) bars as questions of fact. A jury usually determines a factual question. In Kendall v. Winsor, the Supreme Court has held that a jury should decide whether trial evidence is sufficient under the law to cause the loss of patent rights.

In Kendall, an inventor used workers to help test and develop a textile machine. Before completing the invention, one employee left the inventor’s business to build a similar machine for a textile company. The question for the trial jury was whether the inventor’s experimental use of the machine before applying for a patent made the patent invalid. The jury found that the patent was valid because the inventor’s work in his business was experimental, which negated the defendant’s allegation of public use.

The defendant appealed. The Supreme Court held that public use and experimental use were questions of fact and that the law supported the jury’s holding that the patent was valid because Kendall was experimenting with the invention before applying for a patent. The Supreme Court noted that only a jury could properly weigh the many facts needed to determine experimental use. This fact led the Supreme Court to reason that only a jury could determine whether an inventor had proven that experimental use negated a claim of public use. Therefore, the Supreme Court implicitly held that experimental use is a question of fact because jurors can only decide factual questions.


The Federal Circuit took a different approach than the Kendall court regarding whether experimental use is a question of fact or law. Over time, the Federal Circuit decided three cases that eventually led it to conclude that experimental use is a question of law. This section will discuss these three cases to demonstrate the path the Federal Circuit took to lead to its outcome.

Federal Circuit law regarding whether experimental use is a question of fact or a question of law is not entirely consistent. The Federal Circuit has sometimes held that experimental use is a question of fact. At other times the Federal Circuit has held that experimental use is a question of law. Generally, the Federal Circuit has not provided a rationale for choosing one rather than the other. This chain of inconsistency started with one Federal Circuit case, In re Foster.

A. In re Foster

In Foster, the Patent Office Board of Appeals (“Board”) rejected an appeal of a patent denial. The Board denied the appeal because the invention was too obvious to justify a patent. After the applicant appealed, the United States Court of Customs and Patent Appeals, a predecessor to the Federal Circuit, affirmed the Board’s denial of the patent. The only issue before the court was whether the invention, a synthetic rubber material, was an obvious improvement under 103. Section 103 bars patents for improvements that are obvious to anyone familiar with the appropriate field. Thus, if Foster’s rubber material was an obvious improvement, then it would be barred under 103 from patent protection. The Foster court held that the synthetic rubber was only an insignificant, obvious improvement. Foster did not state whether 102(b) bars are questions of fact or questions of law.

B. In re Corcoran

The Court of Customs and Patent Appeals relied on Foster to decide In re Corcoran. Corcoran was an appeal of a Board rejection of a patent on a different issue than the one in Foster. Corcoran involved a combined 102(b)/103 bar. The Board held that an inventor’s competitor sold a device that made Corcoran’s device merely an obvious improvement. The issue was whether the facts supported the Board denying a patent because Corcoran exceeded the one year deadline of 102(b) coupled with the 103 bar. The invention was plastic sheeting for use in window blinds. If Corcoran’s plastic sheeting component was an obvious improvement, then 103 would bar patenting the invention. The Corcoran court affirmed the Board’s denial of a patent because similar plastic sheeting had been on sale, making Corcoran’s later invention only an obvious improvement as a matter of law. The Corcoran court based the decision on the law mentioned in Foster.

The Corcoran court relied on the Foster holding to decide that the coupled question of public use and obviousness is a question of law. However, Foster did not address this issue of public use coupled with obviousness. Its holding related to a completely separate issue — whether obviousness is a question of law.

Neither Corcoran nor Foster was solely an experimental use case. When faced with a purely experimental use case, the Federal Circuit used the Corcoran court’s reading of Foster to decide that all 102(b) bars are questions of law. This mistake became more salient when the Federal Circuit again misinterpreted the law in Barmag Barmer Maschinenfabrik AG v. Murata Machinery, Ltd.

C.Barmag Barmer Maschinenfabrik AG v. Murata Machinery, Ltd.

In Barmag, a machine manufacturer sued a competitor for patent infringement. The parties disputed whether a yarn processing machine was in experimental use. The district court ruled the patent invalid as a matter of law. After Barmag appealed, the Federal Circuit affirmed, finding Barmag’s patent invalid because Barmag violated a 102(b) bar. The Federal Circuit ruled that all 102(b) bars, including public use, are questions of law. Barmag did not refer to Kendall, the Supreme Court precedent that found experimental use is a factual question. Instead, the Barmag court based its ruling on a reading of In re Corcoran. However, Corcoran did not address all 102(b) bars. Corcoran related to a completely separate issue — whether the coupled question of public use and obviousness is a question of law or fact. The Federal Circuit relied on the mistaken analyses in these three cases when it decided Lough v. Brunswick Corp.


Lough v. Brunswick Corp. was a patent infringement dispute over a boat part. A jury found that the defendant infringed the plaintiff’s patent. On appeal, the Federal Circuit reversed and ruled that whether experimental use negates public use is a question of law, properly reserved for a judge to decide.

A. Facts

In 1986, Steven G. Lough was a mechanic for a boat dealership in Sarasota, Florida. As part of his job, Lough worked with Brunswick inboard/outboard motors. While repairing those motors, he noticed that a particular seal often corroded from contact with sea water.

Lough designed a new seal to prevent this corrosion. After making six prototypes, he installed the seals in his boat and in friends’ boats. At trial, Lough claimed that he used the prototypes to test them. For more than a year Lough did not ask anyone if the seals worked well.

Lough did not patent his invention during this time either. Instead, he took more than two years to find out if the seals were adequate. His test results showed that Lough’s seal was superior to any other available at the time. Lough filed for a patent in June 1988 and the Patent and Trademark Office issued a patent a year later.

Lough then sued Brunswick for patent infringement and won a jury verdict. The issue was whether Lough’s testing the seals by placing them in friends’ boats was a public use. The jury found that Brunswick did not prove that Lough’s invention was in public use one year before the patent filing date. The trial court denied Brunswick’s subsequent motion for a Judgment as a Matter of Law. Brunswick had argued that the jury verdict was incorrect because the public use of the invention happened more than one year before Lough filed for a patent.

B. Federal Circuit Decision

In its de novo review upon appeal, the court considered whether the jury properly decided that the use of Lough’s prototypes in 1986 was experimental. The court held that whether an invention was in public use more than a year before applying for a patent under 102(b) is a question of law. The Federal Circuit Court based this holding on Manville Sales Corp. v. Paramount Systems, Inc. In Manville, the Federal Circuit mentioned that experimental use is a question of law. However, the Manville court did not cite authority for this dictum.

After ruling that experimental use was a question of law, the Lough court found that Lough’s six prototypes were indeed in public use. The court reasoned that Lough provided the prototype seals to members of the public for their free and unrestricted use. The Lough court concluded that the jury’s finding of experimental use was incorrect as a matter of law.


The Lough court erred in its ruling. The court did not follow Supreme Court precedent. It incorrectly held that experimental use is a question of law because of a chain of errors. The Lough court should have followed Kendall, which held that experimental use is a question of fact. Instead, the Federal Circuit followed a chain of errors to find that experimental use is a question of law.

A. The Lough Court Incorrectly Chose Not To Follow The Supreme Court’s Kendall Decision

The United States Supreme Court held that experimental use is a question of fact in Kendall. Despite this binding precedent, the Lough court held that public use is a question of law, then compounded that mistake by also holding that experimental use is a question of law. The Supreme Court has already decided the proper analysis for public use and experimental use disputes. The Supreme Court has uniformly treated public use and experimental use as questions of fact. The need for consistency in United States patent law is a compelling reason to follow the Kendall holding that public use and experimental use are questions of fact.

Striving for consistency, the Supreme Court instructed courts to defer to trial courts’ findings of fact when deciding cases involving 102(b) bars. The Supreme Court has never referred to statutory bars only as questions of law. The Supreme Court precedent provided guidance for experimental use questions before the Federal Circuit.

B. Federal Circuit Erred When Reading Foster-Corcoran-Barmag Trio

The Federal Circuit has mistaken its own precedent on experimental use. The mistake in Barmag was the culmination of a chain of errors. In Barmag, the Federal Circuit held that a 102(b) bar is a question of law. Barmag did not refer to Kendall which found that experimental use is a factual question. The Barmag court’s ruling was based on an erroneous reading of In re Corcoran, which the Barmag court thought to state that 102(b) bars are questions of law.

However, In re Corcoran used the label “matter of law” regarding a combined 102(b)/103 question. In other words, the In re Corcoran court never held that a purely 102(b) question was a question of law. Instead, the court cited In re Foster for the proposition that whether a 102(b) bar exists is a question of law.

Foster does not stand for this proposition. Section 102(b) bars were not even at issue in Foster. The only issue before the court was whether the invention was an obvious improvement. If it were an obvious improvement, then it would be barred from patent protection under 103, not 102. Barmag’s weak holding resulted from stacking error upon error.

C. Federal Circuit’s Confusion Led To More Confusion

The Federal Circuit’s confusion in the Foster-Corcoran-Barmag trio led to more confusion. The Barmag court erred in using Corcoran and Foster to hold that courts may reexamine experimental use findings de novo upon appeal. These cases do not address whether 102(b) bars are questions of law or questions of fact. Unaware of this chain of errors, the Lough court committed a remarkably similar error by supporting the holding on experimental use with an unsupported authority.

Lough cited a dictum in Manville as authority for holding that experimental use is a question of law. Manville mentioned this proposition nonchalantly without citing any authority. As it did in the Foster-Corcoran-Barmag trio, the Federal Circuit again stacked error upon error by reading a case out of context. This mistake resulted in the Lough court erroneously holding that experimental use is a question of law. Furthermore, the Circuit’s mistaken interpretation in the Foster-Corcoran-Barmag trio and in Manville should require a Supreme Court reassessment of the experimental use doctrine to restore sense to 102(b) bars.

D. Why Experimental Use Should Be A Question Of Fact

The Supreme Court should reassess the experimental use doctrine by analyzing why experimental use should be a question of fact. The Supreme Court should reexamine its holding in Kendall that a jury should decide questions of experimental use. When a jury decides experimental use under a judge’s guidance, the practice will lead to consistency in experimental use decisions. In Kendall, the Court did not overrule the jury because it reasoned that limitless review of many conflicting facts could result in inconsistent rulings. If the Federal Circuit’s review of a jury decision is unlimited, the Circuit could select and choose various facts and produce inconsistent results, as it did in the Foster-Corcoran-Barmag trio.

Also, if the Federal Circuit could freely reexamine jury findings of experimental use, appeals to the Federal Circuit would likely increase. Appellate courts should minimize case loads by not opening the floodgates to anyone that disagrees with a jury verdict. In sustaining jury findings on experimental use that are not clearly incorrect, the Federal Circuit would prevent wasting lower court resources used to decide experimental use for the first time. Limiting review of jury experimental use decisions would also minimize excessive use of the Federal Circuit’s resources.

However, the Lough court held that applying experimental use as a question of fact to be a mistake. The Lough court explained that juries are unpredictable. The Lough court further commented that appellate findings will provide consistency that jury findings often lack.

Indeed, consistency may be more likely if judges decide questions of experimental use. On different cases with similar facts, different juries could give different verdicts. If judges, patent attorneys, and business people could predict a patent’s validity, appeals on experimental use would be less likely. Consequently, the Lough court held that judges should decide experimental use questions.

However, the Supreme Court aptly considered and rebutted these concerns in Kendall. Congress created the patent system to benefit the public through providing temporary rewards to the inventor in exchange for public disclosure of the technological advancement. Undue deference to a patent challenger may disrupt the bargain between the inventor and the public. As flawed as the jury system is, the best way to determine experimental use is still to have multiple jurors checked by an experienced trial judge.

Prior cases have held likewise after considering inventors’ practices and trial fact-finding procedures. De novo review of experimental use verdicts is difficult and demanding. Since reviewing courts do not have the benefit of the trial testimony, and because frequently conflicting trial evidence requires findings of credibility, experimental and public use should be questions of fact.


In Lough v. Brunswick, the Federal Circuit incorrectly decided that experimental use is a question of law. The Lough court ignored the Supreme Court’s Kendall case and misconstrued other precedent. The ignored case law provides better reasoning and guidance to the use of the experimental use doctrine. Soon the Supreme Court will have the opportunity to adopt a standard on experimental use when it rules on Pfaff v. Wells Electronics. The trier of fact, whether it be a judge or a jury, should determine whether an inventor’s use of an invention before applying for a patent constitutes experimental use.

© 1998 Frederic M. Douglas. All Rights Reserved.

Business Car Leasing Versus Business Car Rental

Business car leasing is arguably the most common type of leasing in modern society, beating out even its equally popular personal variant. This is mostly due to the fact that many companies and corporations choose to have company cars for their employees, and tend to lease the majority of these vehicles from specialist companies.

Still, as common as this process is, there is still a degree of confusion among the non-initiated as to what exactly distinguishes business car leasing from business car rental. It is this distinction that the lines below attempt to make clear, by outlining some of the main differentiating points between the two practices.

Leasing Versus Renting

Before delving into the particularities of business car leasing, it is important to define exactly what is meant by this term, and how it differs from the other popular operation involving the temporary ownership of vehicles, car rental. The answer to this conundrum is actually quite simple, and mostly related to the duration of the contract; specifically, car leases tend to be long-term deals, usually spanning a period of years, whilst car rentals are typically shorter in scope, usually lasting only for a few days or weeks. As such, a car lease involves a significantly higher number of obligations than a car rental, both on the part of the company and on the part of the lessee themselves.

Another major difference between car leasing and car rental has to do with the mile cap on the vehicle. A lease car will typically have an allowance of between 12.000 and 15.000 miles per year, after which the lessee will be required to pay a fee for every extra mile. Similarly, lease cars are subject to depreciation over time, a problem which is not relevant to rental cars, as they will typically change hands frequently, as opposed to once every few years, and tend to not be brand new when rented to customer. Fundamentally, however, both processes are similar, with the amount of time each contract is celebrated for being the main differentiating factor between the two.

What Does Business Car Leasing Entail?

When taking out a car lease, there are typically a number of factors which are non-negotiable, while others can be customised and set to each client’s specifications. The latter tend to include the capitalised cost, leasing’s equivalent to a selling price, the money factor, or interest rate, and the trade in price of any vehicles which may be included in the deal. Non-negotiable factors tend to include residual value, that is to say the value of the car at the end of the deal, and the acquisition fee. Other factors, such as the disposition fee, charged for selling the car at the end of the lease, and the eventual buy-out price for the car, may or may not be negotiable depending on the lease. In the specific case of business car leasing, certain companies may be open to negotiating a bulk price for an entire fleet of cars, so customers should not be afraid to enquire into this possibility.

In addition to these factors, lessees should expect to be charged for extra mileage, as detailed above, and any excessive wear and tear the car may present at the end of the lease. In return, the lessor, that is to say the leasing company, agrees to pay for maintenance and insurance costs for the vehicle for the duration of the lease. It is this latter factor that makes personal and business car leasing so popular, as it often allows both private lessees and companies to save a considerable amount of money in insurance fees and repairs.

It has hopefully become apparent, then, that business car leasing and business car rental are two significantly different types of operations, with significantly different obligations on the part of both the customer and the provider. This knowledge will hopefully help companies know what to expect and how to act when taking out a business car lease.

Sell Junkyard Auto Parts and Make Money From Home

A lot of people make some serious money from home selling junkyard auto parts. My husband’s been doing this for a while now and just loves it! I’m still amazed at how untapped this market is. Maybe because when you sell junkyard auto parts you’re not sitting at a computer all the time?

But working from home doesn’t always mean making money online or just from your computer, especially if you’re doing any type of arbitrage deals.

And there are thousands of people looking for cheap auto parts online. Why not get in the game and be one of their salvage auto parts suppliers?

This is business that you really don’t have be a mechanic or detail specialist to make some real money, especially if you’re just dealing with interior or exterior restoration parts or basic engine parts.

For example, a head rest is a head rest. Unscrew some parts and pull it out. Door panels are door panels. Unbolt them from the hinges and take it off. Engine components may be a bit trickier but you can always go on YouTube and find out what the parts are, what they do and even how to remove them.

But even in this type of a business, you may want to specialize in a niche. What do I mean by a niche when it comes to used auto body parts? Pretty easy. Here are some ways to drill down a niche just by specializing…

  1. … in a particular make and model of vehicle
  2. … in sports cars
  3. … in truck parts
  4. … in engine parts
  5. … in exterior body parts
  6. … in interior restoration parts

Just think about all of the parts that go into building a vehicle, whether it’s a truck or car. Some parts are even interchangeable between makes and models. For example, I needed a new front fender for my 2001 Mercury Villager. Did you know that the 2001 Nissan Quest has an identical body to the same year Mercury Villager?

They do! So my husband took the parts off of a junked Quest and replaced the fender and front light assembly on my Villager.

The cup holder assembly in my Villager cracked too. But instead of replacing that unit, he found a narrow console with built-in cup holders from a Dodge SUV that fit perfectly between the front bucket seats of our Villager. Same color and texture as the interior of our car; that console looks like it came with our van!

So now we have three “new” cup holders in the front, and two additional cup holders for the rear seat, from one $10 used Dodge console.

You will have to do some research on eBay before going out and spending money. You can’t just go out and buy any junkyard auto parts and expect them to sell. There are some steps involved to making this a profitable at-home business.

  1. First, get a price list from your local salvage yard. Look for the least expensive parts on the list.
  2. Look up the parts on eBay and filter by Sold listings. Take an average of what those parts are selling for and see what your profit margin is. For example, if it’s going to cost you $10 to buy the part and it’s selling on average of $85 or more, and there are a lot of them being sold, you’ve got a winner.
  3. Take into consideration how much time and effort you want to put into pulling the parts off the vehicles. Some parts are pretty easy and you’ll only need a couple of screw drivers on hand. Other parts can be rather tricky, depending on whether you’re dealing with interior, exterior or under-the-hood parts.
  4. Another thing to think about is the weather! Here on the east coast it gets really blustery during the winter. And in the spring, it can get pretty muddy out in the yard. So you need to make sure you’re dressing for the weather – be prepared for anything.