How to cite a patent is dependent on the citation style you are using. Please see some examples below. Always check with your instructor, editor, or publisher to know which citation format to use. 

NOTE: When citing a patent, make sure the Patent Number exactly follows the document, including all commas, spaces, and dashes.

Examples of how to cite U.S. Patent 3,005,282 using five different citation styles:

1. ACS (American Chemical Society)
2. APA
3. Chicago Manual of Style
4. IEEE
5. MLA

ACS (American Chemical Society) (3rd edition, 2006, page 310)

Format: 

Patent Owner(s). Title. Patent Number, Date.

Example: 

Christiansen, G.K. Toy Building Brick. U.S. Patent 3,005,282. Oct. 24, 1961.

APA style (7th edition, 2020, page 366)

Format: 

Inventor, A. A. (Year issued). Patent Identifier Number. Location: Source Name.

Example: 

Christiansen, G.K. (1961). U.S. Patent 3,005,282. Washington, DC: U.S. Patent and Trademark Office.

In-text: (U.S. Patent No. 3,005,282, 1961)

Chicago Manual of Style (17th edition, 2017, section 14.258)

Format: 

Names, Creator. Patent title. Patent number, and year of filing.

Example: 

Christiansen, Godtfred Kirk. Toy building brick. US Patent 3,005,282, filed July 28, 1958, and issued October 24, 1961.

IEEE (Institute of Electrical and Electronics Engineers) (V 01.29.2021, Section J)

Formats: 

J. K. Author, "Title of patent," U.S. Patent x xxx xxx, Abbrev. Month, day, year.
J. K. Author, "Title of patent," Country Patent xxx, Abbrev. Month, day, year.

NOTE: Use "issued date" if multiple dates are given.

Format (for online patent):

Name of the invention, by inventor’s name. (year, month day). Patent Number [Type of medium]. Available: site/path/file

Example:

G.K. Christiansen, "Toy building brick," U.S. Patent 3,005,282, Oct. 24, 1961.

Toy building brick, by G.K. Christiansen. (1961, Oct. 24). U.S. Patent 3,005,282 [online]. Available: https://patents.google.com/patent/US3005282A/en

MLA

NOTE: MLA style manual does not provide information on citing patents specifically however, it can be inferred based on other electronic resources.

Formats: 
Inventor(s). Title of Patent. Date Issued. U.S. Patent number. Title of Website or Repository, URL. Accessed Day Month Year.

Inventor(s). Title of Patent. Date Issued. U.S. Patent number.

Example: 
Christiansen, G.K., inventor. Toy Building Brick. 24 Oct. 1961. U.S. Patent 3,005,282. Google Patents, https://patents.google.com/patent/US3005282A. Accessed 15 Feb. 2019.

In-text: (Christiansen)