SF-0012Products Invented Because Someone Had Enough
The laser-pointer cat patent specifies the dot must be small relative to the cat's paw
US 5,443,036 was granted in 1995. Its dependent claims are the reason to read it: the light pattern must be small relative to a cat's paw, and travel at five to twenty-five feet per second.
Illustration — not a photograph, and not evidence for anything on this page.
Figure 1 of the patent: the cat owner, the hand-held laser, the beam, and the cat pursuing the light pattern where it meets the floor.
FIG. 1 is a perspective view of a cat owner exercising a cat in accordance with the present invention." The numerals are the specification's: 10 the laser apparatus, 12 the cat owner, 14 the invisible beam, 20 the cat, 22 the bright pattern of light.
- Image
- Kevin T. Amiss and Martin H. Abbott (inventors); drawing published by the USPTO
- Taken
- 1995-08-22
- Archive ref.
- US Patent 5,443,036 — drawing sheet 1, Figure 1
- Licence
- Text and drawings typically not subject to copyright restrictions under USPTO policy; no exception applies to this patent on inspection (licence record)
- The image itself
- Authentic, unaltered
Figure 1, US Patent 5,443,036 (Amiss and Abbott, "Method of exercising a cat", issued 22 August 1995). United States Patent and Trademark Office. Cropped from drawing sheet 1.
Verdict
"Someone actually patented playing with a cat using a laser pointer."
The claim is supported by primary or authoritative evidence, and nothing of comparable quality contradicts it.
Established by the patent itself, read in full from the USPTO's own four-page scan. US 5,443,036 was granted to Amiss and Abbott on 22 August 1995 on application 144,473 filed 2 November 1993, classified A01K 29/00, with four claims and one drawing sheet, examined by Todd E. Manahan. The claim being tested is that such a patent exists and covers that method; the document answers it directly and nothing of comparable quality contradicts it.
Scoped tightly on purpose. "A patent was granted" is the whole of the verdict. It is not a finding that the method was novel in any practical sense, that the health benefits the specification asserts are real, that the invention was ever commercialised, or that pointing a laser at a cat is good for the cat. The patent is evidence of examination, not of efficacy, and this file says so.
Verified requires 1 primary or authoritative source. This file cites 2.
In short
In 1993 Kevin T. Amiss and Martin H. Abbott filed a patent application for exercising a cat with a laser pointer. It was granted on 22 August 1995 as US 5,443,036, with four claims, one drawing sheet, and a discussion of prior art that considers string, yarn, a bouncing ball and sunlight redirected through a prism — rejecting the last for "the uncertainty of collecting a convenient sunbeam". The patent is real and its claim language is precise. What it does not establish is that the method was novel in practice, beneficial, or safe.
What was actually granted
On 22 August 1995 the United States Patent and Trademark Office granted patent 5,443,036 to Kevin T. Amiss of Alexandria and Martin H. Abbott of Fairfax, Virginia. The title is Method of exercising a cat. It has four claims and one drawing sheet, and it was examined by Todd E. Manahan.
Claim 1 covers a method of inducing aerobic exercise in an unrestrained cat: direct a coherent beam of invisible light from a hand-held laser onto an opaque surface so as to produce a bright pattern “of visual interest to a cat”, then redirect the beam out of the cat’s reach so the animal chases the pattern around an exercise area.
The dependent claims are the good part
Claim 2 narrows the invention to the case where the bright pattern of light “is small in area relative to a paw of the cat”. The unit of measurement is a paw.
Claim 4 specifies sweeping the beam so the pattern travels “at a speed in the range of five to twenty-five feet per second” — and the specification explains why there is an upper bound: fast enough to exert the cat, but “not so discouragingly fast as to dissuade against the chase.”
Claim 3 covers the case where the beam stays invisible until it hits the surface. It looks at first like a drafting error sitting next to a “bright pattern of light”, and it is not one: the beam is invisible in the air and the spot where it lands is not. The joke that isn’t there is worth naming, because it is the one this file nearly made.
The prior art
The background section is where the document stops being a legal instrument and starts being comedy, entirely straight-faced. It opens: “Cats are not characteristically disposed toward voluntary aerobic exercise. It becomes the burden of the cat owner to create situations of sufficient interest to the feline…”
It then works through the alternatives. String and yarn. A ball rolling across a floor. Sunlight reflected off a mirror or focused through a prism — rejected, in a phrase worth the whole patent, for “the disruption of having to darken a room to stage a cat workout and the uncertainty of collecting a convenient sunbeam.”
Under Other Publications the file cites two real neuroscience papers on feline visuomotor performance, from Psychopharmacology and Behavioral Brain Research.
What this file does not claim
That the method was novel in any practical sense — the specification’s own prior-art section concedes people were already moving lights for cats to chase. That it works, or is healthy: the patent asserts cardio-vascular, respiratory, weight and muscle-tone benefits, and that is an applicant’s assertion in a patent application, not a veterinary finding. That it is safe for the cat or the person: laser safety has real standards and this file has not read them, so it says nothing.
A patent is evidence that an examiner found a claimed combination allowable. That is a narrower and more procedural fact than “someone invented this”, and it is the fact this file reports.
The evidence
US Patent 5,443,036, "Method of exercising a cat", was granted to Kevin T. Amiss of Alexandria and Martin H. Abbott of Fairfax, Virginia on 22 August 1995, on application 144,473 filed 2 November 1993. Four claims, one drawing sheet. Primary examiner Todd E. Manahan.
Cited sources:S1
Claim 1 covers "A method of inducing aerobic exercise in an unrestrained cat" by directing an intense coherent beam of invisible light from a hand-held laser onto an opaque surface to produce a bright pattern "of visual interest to a cat", then redirecting the beam out of the cat's reach to induce it to chase the pattern around an exercise area.
Cited sources:S1
Claim 2 narrows the invention to the case where "said bright pattern of light is small in area relative to a paw of the cat". The dependent claim is measured in cat paws.
Cited sources:S1
Claim 4 specifies sweeping the beam so the pattern moves "at a speed in the range of five to twenty-five feet per second". The specification explains the range: fast enough to exert the cat, "but not so discouragingly fast as to dissuade against the chase".
Cited sources:S1
Claim 3 covers the case where the beam "remains invisible between said laser and said opaque surface until impinging on said opaque surface" — which is why the specification's "invisible light" producing a "bright pattern" is not a contradiction. The beam is invisible in transit; the spot where it lands is not.
Cited sources:S1
The prior-art discussion considers hand-held string or yarn, a rolling ball, and sunlight reflected from a mirror or focused through a prism. It rejects the sunlight approach on practical grounds: "The disruption of having to darken a room to stage a cat workout and the uncertainty of collecting a convenient sunbeam."
Cited sources:S1
The specification opens by asserting a problem: "Cats are not characteristically disposed toward voluntary aerobic exercise. It becomes the burden of the cat owner to create situations of sufficient interest to the feline to induce even short-lived and modest exertion."
Cited sources:S1
Two academic papers on feline visuomotor performance appear under Other Publications — Carayan et al. in Psychopharmacology (1991) and Levesque et al. in Behavioral Brain Research (1990) — alongside eight cited US patents.
Cited sources:S1
Evidence that cuts the other way
Findings that complicate or argue against the verdict above. They are listed because leaving them out would make the file look stronger than it is.
The specification asserts the method exercises the cat "to the cardio-vascular, respiratory, weight control, and muscle tone benefit of the animal" and calls it healthy. That is the applicants' assertion in a patent application, not a veterinary finding, and this file does not repeat it as fact. A patent is examined for novelty, utility and non-obviousness — not for whether its health claims survive scrutiny.
Cited sources:S1
A granted patent is not evidence that a method was unknown before it. People had been moving lights for cats to chase for as long as both have existed, and the specification concedes as much by discussing string, balls and sunbeams as prior art. What the grant establishes is that an examiner found this particular claimed combination allowable — a narrower and more procedural fact than "nobody had thought of it".
Cited sources:S1
What we still don’t know
- Whether the method is good for cats. The patent asserts cardio-vascular, respiratory, weight and muscle-tone benefits; nothing was consulted that tests those assertions, and no veterinary source was read. The file therefore attributes the claim to the applicants and takes no position on it.
- Whether laser pointers are safe to use this way, for the cat or the person. Not researched and not addressed. Laser safety is a real subject with real standards and a file that gestured at it without reading them would be worse than one that says nothing, so this file says nothing.
- Whether the patent was ever commercialised, licensed or enforced. Not established. Laser cat toys are ubiquitous, but their existence is not evidence that they practise this patent or derive from it, and no attempt was made to connect the two.
- When the patent lapsed. A 1993 filing granted in 1995 falls near the boundary between the old seventeen-years-from-issue term and the twenty-years-from-filing term, and maintenance-fee history was not checked. Nothing in this file depends on the expiry date, so no date is asserted.
Sources
Every source below was read in full before it was cited. Archive snapshots are recorded at research time, because a file whose sources have evaporated is indistinguishable from one that never had any.
S1Tier 1Read in full
US Patent 5,443,036 — Method of exercising a cat
Kevin T. Amiss and Martin H. Abbott · United States Patent and Trademark Office · 1995-08-22
The patent itself, retrieved as the USPTO's own four-page scan and read in full — front page, drawing sheet, specification and all four claims. It is the document the claim is about, and it establishes every finding here directly: the parties, the dates, the classification, the examiner, the claim language including the paw comparison and the speed range, the prior-art discussion, and the cited literature. Also the source of the image, and the subject of the rights inspection.
S2Tier 1Read in full
Terms of Use for USPTO Websites
United States Patent and Trademark Office
The agency's stated rights position: that patent text and drawings are "typically not subject to copyright restrictions", subject to exceptions at 37 CFR 1.71(d)–(e) and 1.84(s); that not all material on USPTO sites is US government work; and that the seal and logo are excluded. Cited for the licence reasoning only, and load-bearing here in a way it was not for the 1868 patent, because this document has no term-expiry fallback.
Checked for circularity: S1 and S2 were confirmed not to derive from one another. Two sources that trace back to the same origin are one source, and counting them twice is the most common way a false claim looks well-evidenced.
How we checked this
What we went looking for, and what we found
Three searches against this file's own framing, two of which changed it.
First, against the temptation to call the patent's language incompetent. "A beam of invisible light" producing "a bright pattern of light" reads at first like a drafting blunder, and it would have made a sharper card. Claim 3 settles it the other way: the beam is invisible between the laser and the surface until it impinges on it. That is correct physics, and the file abandoned the funnier reading because it was the wrong one.
Second, against the rights position. Text extraction reported no copyright notices; the extraction had produced four bytes from a scanned document, so the clean result was a false negative rather than a clearance. All four pages were re-inspected visually. The conclusion survived, but it survived on evidence rather than on a null.
Third, against "nobody had thought of this before". The specification itself discusses string, balls and sunbeams as prior art, so the grant cannot mean the idea was unknown — only that this claimed combination was allowable. Recorded as contradicting evidence.
- We searched for evidence against our own conclusion
- We traced where the claim started
- The claim is stated in its strongest form, not a weak version
- The photograph was verified independently of the story
- We checked whether this was settled after the popular version froze
- Image rights were traced to a stated licence
- We checked what we were leaving out
- The verdict sat before publication, and was re-read cold
- Confidence in the verdict
- high
- Verdict assigned
- Most recent authoritative source
- Researched by
- The Strange File
NOT YET CLEARED, and the reason is recorded because the record was briefly wrong.
An earlier version of this file named a second reviewer and treated cooling-off as satisfied by that review. Both were incorrect and both are retracted.
What actually happened: a narrow comment was made on one isolated question — the copyright cut-off year in SF-0011, and the invisible-beam reading plus the need to avoid unsupported safety claims in SF-0012. Nobody inspected the full dossier, the evidence packet, every source, the image-rights record, the verdict reasoning, the captions, the cards or the motion asset. A reviewer answering one question is not a reviewer approving a file, and inferring the second from the first is precisely the move this publication exists to catch other people making.
Cooling-off is also not the same control as independent review, and this file will not treat it as one. Cooling-off is a wait, and the wait has elapsed. The verdict was assigned 2026-07-30; the fresh-eyes pass was made on 2026-07-31 by a session that neither researched nor wrote this file, reading the dossier, the evidence, the sources, the verdict reasoning and the rights record cold. The pass changed one thing. The headline read "smaller than the cat's paw", while claim 2 — quoted correctly three times elsewhere in this file — says the pattern is "small in area relative to a paw of the cat". Those are different assertions: one is a dimensional comparison, the other a proportion. A file whose whole subject is the precision of claim language must not paraphrase that language loosely in the one line most likely to be quoted back. Corrected to "small relative to".
That pass is cooling-off and nothing else. A cooling-off reader is not an independent reviewer, and this file names no second reviewer — it carries no sensitivity flag, so none is required. The owner has not approved publication, and READY is not permission to publish.
Three separate controls, none of which may stand in for another: the cooling-off wait, independent review, and the owner's approval. Neither of the last two has occurred.
The two named inventors are private individuals and may well be living, but the file makes no claim about them beyond what the patent record states — that they filed and were granted this patent — which is a public act recorded in a public document. No sensitivity flag is set on that basis, and it was considered rather than skipped.
Part of a collection
What The Stamp Actually CertifiesA grant, a listing, a prize. Each certifies something narrower than everyone reads it to mean.
Patently AbsurdReal patents, examined and granted, for things nobody needed.
Also related
The 1868 escape coffin had a bell, a ladder, and a tube you took back afterwards
Franz Vester patented a coffin the prematurely buried could climb out of. The detail nobody repeats is in the specification: once death was confirmed, you withdrew the escape tube and used it on the next grave.
The high-five patent treats the high five itself as previously known prior art
US 5,356,330 was granted in 1994 for a spring-loaded arm on a wall. Its background states the problem plainly: a high five "requires the mutual hand slapping of two participants", and a solitary fan does not have two.