Blank check

A blank cheque or carte blanche (US: blank check), in the literal sense, is a cheque that has no numerical value written in, but is already signed. In the figurative sense, it is used to describe a situation in which an agreement has been made that is open-ended or vague, and therefore subject to abuse, or in which a party is willing to consider any expense in the pursuance of their goals.

Cheque writers are advised to specify the amount of the cheque before signing it. A blank cheque can be extremely dangerous for its owner, because whomever obtains the cheque could write in any amount of money, and would be able to cash it (to the extent that the checking account contains sufficient funds, and depending on the laws in the specific country). Under American law, a blank cheque is an example of an incomplete instrument as defined in the Uniform Commercial Code's Article 3, Section 115 (a). Writing an amount in a blank cheque, without the authority of the signer, is an alteration. It is legally equivalent to changing the numbers on a completed (non-blank) cheque.

In finance, a blank cheque company refers to a company in development that has no specific business plan, such as a special purpose acquisition company.

In March 2003, Gordon Brown, then Chancellor of the Exchequer, "effectively offered a blank cheque for war against Iraq", and would thus '"spend what it takes" to tackle Iraq's weapons of mass destruction.'

Sir Arthur Conan Doyle used the term carte blanche in several of his Sherlock Holmes stories.

“Then, as to money?”

“You have carte blanche.”

“Absolutely?”

“I tell you that I would give one of the provinces of my kingdom to have that photograph.”

"I understand that you give me carte blanche to act for you, provided only that I get back the gems, and that you place no limit on the sum I may draw.”

“I would give my fortune to have them back.”

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Wikipedia