There is a common misunderstanding that patents have to work to be patented.

This is not true.

United States patent laws do not require you to have a prototype in order to apply for a patent, all that is required is that you be able to describe the invention so that others could both make and use it.

So people can make claims about how their invention should work, without ever offering empirical evidence that they do. (Anecdotally, I am the author of several patents for inventions that have never, and probably will never, exist.)

Patents are not peer-reviewed by active scientists but by patent clerks. They tend to have a technical background (in Europe, they need a degree in science or engineering).

The reviews they perform may be less than thorough:

On April 13, 2007, a "Coalition of Patent Examiner Representatives" expressed concern that

in many patent offices, the pressures on examiners to produce and methods of allocating work have reduced the capacity of examiners to provide the quality of examination the peoples of the world deserve [and that] the combined pressures of higher productivity demands, increasingly complex patent applications and an ever-expanding body of relevant patent and non-patent literature have reached such a level that, unless serious measures are taken, meaningful protection of intellectual property throughout the world may, itself, become history.

As a result, it is easy (albeit a little expensive) for pseudo-scientists to try to gain credence by obtaining a patent.

It is not hard to name an area of pseudo-science, and find patents with unsupportable claims.

I chose some random pseudoscience topics and searched the patents for statements that are likely to make a skeptic scoff:

Homeopathy

Second patent I looked at:

Homeopathy treatment is constitutional; hence there is deep level of healing and recovery. It offers long lasting cure instead of temporary relief and is absolutely harmless, safe and non-toxic.

Crystal Therapy

First patent I looked at:

Famous Ming Dynasty physician Li in the "Compendium of Materia Medica," said the "Sim cold non-toxic," attending "panic and heart heat," can "An Xinming head, to the red eye, Auge swollen ,, etc. can also heal" lung abscess pus spit, Keni on gas "," benefits hair, Yue color "and so on, with extreme major medical function of natural crystal has a special" piezoelectric effect. "impeccable crystal single crystal processed into the human body jewelry to wear, Friction can occur with the body strong electromagnetic fields, such electromagnetic field has a solid feel, the body energy concentration, reduce patient pain and speed recovery speed and other functions, such as American Studies Center praised the "crystal therapy" is the crystal pressed injury patients play the role of adjuvant therapy to the affected area.

Note: This was auto-translated.

Colour Therapy

First patent I looked at

Light therapy works by influencing the effect on treated body part not only with the wavelength of the light (i. e. the own vibrational properties of the light), but also utilising other effects caused by the special photon energy quanta. Moreover, during application of the crystal lamp according to the invention, light energy and crystal energy positively interferes with each other. Irradiation treatments were conducted on patients with light having the spectrum given above. The patients were suffering from emotional disturbances. The irradiation treatments were conducted with double blind control method. In the treatments 20-20 patients were selected having similar mental hygienic problems. Main complaints were anguish, insomnia, chronic nervousness, reduced intellectual capabilities.

The treatments were administered twice daily, for 5-5 minutes at a time. The treatments were made with following parameters: 10 patients received treatment with various colours, and 10 patients were treated with neutral (white) light. The same treatments were made with a known colour lamp, but without the crystal having a pointed apex according to the invention. The evaluation of the behaviour of the patients was made by a mental hygienic professional, different from the person administering the treatments. The evaluation of the results were based on this background, also taking into account the semi-subjective evaluation of the visual- analogue scale (VAS scale), and the reports of the patients themselves. Experience showed that the therapy conducted with the pointed crystals caused approximately 20% more significant therapeutic effect, as compared with the treatments conducted with the previously applied blunt-pointed radiators. In the treatment of certain psycho-somatic symptoms, the effects of the colour stimulation performed with the colour therapy lamp of the invention came close to the treatment effect of a traditional acupuncture treatment, made with needles.

Acupuncture

First patent I looked at was about using acupuncture to cure hair loss:

The acupuncture treatment of the present invention was tested on some 154 cases--127 male patients and 27 female patients. [...] The tests showed positive results in 95% of the patients treated regardless of age and race. A cessation of hair loss was observed on average two to four weeks from the initiation of treatment. New hair growth was noted after an average of four to six weeks. This initial hair loss is thin, short and with less pigment.

I could continue, but that should suffice as evidence that it is not hard to find dubious scientific claims in patents.

Of course, these are anecdotal results. It may well be that a vast majority of patents only contain scientifically acceptable claims. However, they should be sufficient enough to conclude that patents do not serve as a definitive source of information, and should be treated with some skepticism as a source.

Naturally, if the question was about "Did Alexander Bell invent the telephone?", it would be quite appropriate to point to patent filing dates, and the legals claims, without accepting any of the scientific claims included.