Used and loved by millions
Since I tried Ludwig back in 2017, I have been constantly using it in both editing and translation. Ever since, I suggest it to my translators at ProSciEditing.

Justyna Jupowicz-Kozak
CEO of Professional Science Editing for Scientists @ prosciediting.com
duly signed by
Grammar usage guide and real-world examplesUSAGE SUMMARY
The phrase "duly signed by" is correct and usable in written English.
It is typically used in legal or formal documents to indicate that a document has been properly signed by the relevant parties. Example: "This agreement shall be effective upon being duly signed by both parties."
✓ Grammatically correct
News & Media
Science
Wiki
Table of contents
Usage summary
Human-verified examples
Expert writing tips
Linguistic context
Ludwig's wrap-up
Alternative expressions
FAQs
Human-verified examples from authoritative sources
Exact Expressions
4 human-written examples
This document was duly signed by me, countersigned by a notary public.
News & Media
Of the 8.1 million letters that were distributed, the Election Commission got back nearly 7.1 million duly signed by the parents of these students.
News & Media
"Rosegar provides contracts to all employees and retains one copy of the contract duly signed by the employees and by the company".
News & Media
On 7 September 1701, the Treaty of the Second Grand Alliance was duly signed by England, the Emperor, and the Dutch Republic to thwart the ambitions of Louis XIV and stem Bourbon power.
Wiki
Human-verified similar examples from authoritative sources
Similar Expressions
55 human-written examples
Duly signed patient consent forms were obtained that had been approved by the Institutional Review Boards of Tulane Health Science Center, the University of Rochester School of Medicine, and the University of Mississippi Medical Center in Jackson.
Science
Ernst duly signed the frescos, for a fee.
News & Media
The Clinton administration took part in all good faith; the treaty was duly signed.
News & Media
An umptysquillionth album by the son of the man who discovered Bob Dylan, a veteran bluesman with all the payable dues duly signed and docketed except for the unfixable fact of his whiteness.
News & Media
Keane duly signed them, becoming their manager, booker, producer, label boss and publisher.
News & Media
Why would I go anywhere else?'" The centre-half, like James McArthur, duly signed new terms.
News & Media
Vigorous competition sent the period print, duly signed, dated and titled on the back, climbing to €1,915.
News & Media
Expert writing Tips
Best practice
When using "duly signed by", ensure the document's signing process adheres to the required legal and formal standards. Provide context indicating the roles or authority of the signing parties.
Common error
Avoid using "duly signed by" when the signing process doesn't meet the expected standards for legal or formal validity. It's important that all signatures are obtained correctly and without coercion to properly use the term.
Source & Trust
88%
Authority and reliability
4.1/5
Expert rating
Real-world application tested
Linguistic Context
The phrase "duly signed by" functions as a modifier, indicating that a signature has been affixed to a document or agreement in a legally correct and valid manner. As supported by Ludwig, the phrase is used to emphasize the authenticity and validity of a signed document.
Frequent in
News & Media
33%
Science
33%
Wiki
34%
Less common in
Encyclopedias
0%
Formal & Business
0%
Reference
0%
Ludwig's WRAP-UP
The phrase "duly signed by" is a modifier used to assert the legal correctness and validity of a signature on a document. According to Ludwig, the phrase is grammatically correct and appropriate in formal contexts like legal documents, academic papers, and business agreements. While relatively infrequent, "duly signed by" enhances the credibility of a signed item by suggesting adherence to procedural correctness. Alternatives such as "properly endorsed by" or "formally approved by" can be used to convey a similar meaning. The consistent usage of "duly signed by" across News & Media, Science, and Wiki sources signals its broad applicability in scenarios requiring emphasis on legal and procedural correctness.
More alternative expressions(10)
Phrases that express similar concepts, ordered by semantic similarity:
properly endorsed by
Replaces "signed" with "endorsed" and "duly" with "properly", emphasizing approval.
formally approved by
Substitutes "signed" with "approved" and "duly" with "formally", highlighting official authorization.
officially authorized by
Replaces "signed" with "authorized" and "duly" with "officially", stressing the legitimate sanction.
validly executed by
Replaces "signed" with "executed" and "duly" with "validly", focusing on the legal correctness of the signing.
legally attested by
Substitutes "signed" with "attested" and "duly" with "legally", emphasizing the legal witnessing of the signature.
authentically validated by
Replaces "signed" with "validated" and "duly" with "authentically", focusing on confirmation of genuineness through signing.
rightfully ratified by
Replaces "signed" with "ratified" and "duly" with "rightfully", stressing the correct and legitimate approval.
appropriately countersigned by
Replaces "signed" with "countersigned" and "duly" with "appropriately", emphasizing that another signature has been added for validation.
duly ratified by
Focuses only on the ratification aspect, dropping explicit mention of the signing action.
effectively endorsed by
The adjective 'effective' is used to specify the effect of the sign.
FAQs
What does "duly signed by" mean in a legal context?
In a legal context, "duly signed by" signifies that a document has been signed correctly and in accordance with all applicable legal requirements, indicating its validity and enforceability.
What are some alternatives to "duly signed by"?
Some alternatives include "properly endorsed by", "formally approved by", or "officially authorized by" depending on the specific nuance you want to convey.
When is it appropriate to use "duly signed by" in a sentence?
It is appropriate to use "duly signed by" when referring to a document that requires formal or legal validation through signatures. It is often used in contracts, consent forms, and official agreements.
Is there a difference between "signed by" and "duly signed by"?
"Signed by" simply indicates that a signature is present. "Duly signed by" implies that the signature was made correctly, legally, and with proper authorization, adding a layer of formality and validation.
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Table of contents
Usage summary
Human-verified examples
Expert writing tips
Linguistic context
Ludwig's wrap-up
Alternative expressions
FAQs
Source & Trust
88%
Authority and reliability
4.1/5
Expert rating
Real-world application tested