Counterfeiter

To counterfeit means to imitate something. Counterfeit products are fakes or unauthorised replicas of the real product. Counterfeit products are often produced with the intent to take advantage of the superior value of the imitated product. The word counterfeit frequently describes both the forgeries of currency and documents, as well as the imitations of items such as clothing, handbags, shoes, pharmaceuticals, aviation and automobile parts, watches, electronics (both parts and finished products), software, works of art, toys, and movies.

Counterfeit products tend to have fake company logos and brands (resulting in patent infringement and/or trademark infringement in the case of goods), have a reputation for being lower quality (sometimes not working at all) and may even include toxic elements such as lead. This has resulted in the deaths of hundreds of thousands of people, due to automobile and aviation accidents, poisoning, or ceasing to take essential compounds (e.g. in the case a person takes non-working medicine).

The counterfeiting of money is usually attacked aggressively by governments worldwide. Paper money is the most popular product counterfeited.

Counterfeit money is currency that is produced without the legal sanction of the state or government and in deliberate violation of that country's laws.

The United States Secret Service, mostly known for its guarding-of-officials task, was initially organized primarily to combat the counterfeiting of American money. Counterfeit government bonds are public debt instruments that are produced without legal sanction, with the intention of "cashing them in" for authentic currency or using them as collateral to secure legitimate loans or lines of credit.

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Wikipedia