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  • Writer's pictureDavid Morris

FAKE or FORTUNE? Agatha Christie signatures.

For collectors of Agatha Christie books, plays, photos and ephemera, anything signed will always be appealing and increase its value. However, forgers are well aware of this increase in value and as such buyers of signed items must be especially cautious. The documentary series ‘Fake or Fortune’ revealed that as much as 40% of collectible paintings in circulation are forgeries. Given the ease with which signatures can be forged in comparison to a painting, it should cause collectors of anything purported to be signed by Christie to be exceptionally cautious.

Fake or Fortune? Our opinion is at the end of the article.

Here at Collecting Christie we can only provide general guidance, considerations and observations. We are not experts in authentications and nothing we say should be construed to imply a signature is fake or real. We hope the information and all the signature samples below make our readers more informed and thus less susceptible to acquiring forged items.


The most compelling attributes a signature can have is ‘Provenance’ – essentially a trail of documentation that proves authenticity. Provenance is far superior to ‘Stated Authenticity’ (discussed below). Since Agatha Christie’s death, buyers of signed items should seek to connect its history back to when it was signed. From our perspective, the quality of provenance ranges significantly. Signed letters purchased directly from the person to whom they were sent, or inscribed books bought directly from the dedicatee all rank highly for their provenance. Buyers should also ask for the seller to provide a written signed bill of sale (or similar) documenting the transfer of ownership to keep the chain of provenance intact.

Reputable dealers and auctions houses may be able to provide specifics on the chain on ownership and they should be asked for it when not included as part of an item’s description or listing. Private parties should also be scrutineered for their ownership trail. The inability for any vendor to provide historical documentation of the ownership chain should raise red flags. A key learning here for collectors should also be to maintain and preserve the trail of provenance when acquiring items as it will increase the price for which the item can be resold in the future.

Stated Authenticity:

When provenance does not exist, a vendor may offer ‘Stated Authenticity’ – basically a claim of the signature’s genuineness. This claim could be made by the vendors themselves or via a company that specializes in certifications. A claim solely by the vendor should generally be discounted heavily with a few exceptions. A well-established auction house or dealer with a history of trading Christie items certainly ranks higher than those with less experience.

Likewise, a private party’s claim without any provenance can mostly be viewed as worthless. Respected firms that offer independent third-party assessments and certifications of authenticity (COA), such as Beckett or PSA, can provide a professional certification of an Agatha Christie signature for $150 US. If a collector has a signed item, investing in a Beckett or PSA certification would likely allow for a stronger value to be realized when sold. Such a certification provides some confidence to a buyer. Online sites such as eBay now require significant supporting documentation for a seller to claim a COA exists. However, these firms have minimal long-term financial risk to themselves and while they are experienced, a buyer’s due diligence should also include an assessment of the items discussed below.

Signature Norms:

Over Agatha Christie’s lifetime her signature changed, just as everyone’s does. However, by comparing signatures from items with strong provenance during specific periods of Christie’s life norms and characteristics can be established. These attributes can provide the information buyers can use when determining the likelihood that a signature is authentic. One of the unique considerations for Agatha Christie is that she had several different signatures during her lifetime. These were ‘Agatha’, ‘Agatha Christie’, ‘Agatha Mallowan’, ‘Agatha Christie Mallowan’, and ‘Mary Westmacott’.

One of the norms that is apparent is that when she inscribed books to close friends or family she mostly wrote “from Agatha”. Any inscribed book or item to a close friend that is signed “Agatha Christie” (or Mallowan) should be considered abnormal. In addition, inscriptions were often brief. There are a few cases where an additional sentence is added, but this is quite abnormal. While atypical does not mean forged, buyers should be more skeptical if additional provenance is not provided. To business acquaintances or people she interacted with on a professional basis, she would often follow the inscription with “from Agatha Christie”.

Blue Ink:

In reviewing many signatures, it is also clear that blue ink is the most common Christie used. Early signatures pre the mid-1940s often used blue fountain pen ink, and thus should be faded if authentically old. Anything done in fountain pen ink that is unfaded but believed to pre-1940 should be viewed with caution. In addition, anything post-mid-1940s not in blue ballpoint would be atypical, especially if it appears to have been signed or written from home.

Another norm was generic non-author business related correspondence, once married to Max Mallowan, was generally signed “Agatha Mallowan”. Replies to fan letters or items related to her status as an author were generally signed “Agatha Christie”.

Late in life (1970s), her letters were mostly typed by her personal secretary who then made a pencil notation of either “C” or “M” to indicate whether she should sign the letter as ‘Agatha Christie’ or ‘Agatha Mallowan’. Occasionally letters show up for sale with solely the penciled C or M – or with it showing under the signature un-erased. If solely the C or M show, these are not signed items.

A late-life prepared letter with the pencilled "M" that Christie signed over.

A prepared letter with a penciled "C" that Christie forget to sign but was posted anyway.

The Slash Line:

Many signatures also have a slash line underlining the autograph. Of note, in almost all cases of highly authentic signatures with this slash she affixed a dot (.) just above the right end of the line implying the line stroke was from left to right and then finished with a period punctuation mark.


In general, confidence is a norm. Most signatures have a smooth, rapid and flowing style consistent with someone likely asked to sign their name frequently. All letters are generally connected together with the pen never leaving the paper except for the horizontal line for her ‘t’. By looking at a signature to observe its adherence to norms, a more informed perspective can be achieved.

Signature Characteristics:

It addition to norms, there are characteristics within a signature that can also provide insights into its potential authenticity. A few examples of these characteristics are discussed below.

The “g” in Agatha:

Throughout her life, signatures with significant provenance appear to always have a ‘g’ where the loop goes to the right and up, circling back anti-clockwise and then moving straight down in a confident movement (akin to 'p'). Almost every signature with strong provenance in the 1920s-1960s has this style of 'g'. While the signature used by her publishers in various book editions with a printed signature show a more traditional 'g' shape, we hypothecate that the publisher wanted a sample where each letter was clear and obvious as this is not how she signed her name usually.

The "g" in this Agatha is the predominant style throughout her life.

Even in the 1970s there were personal letters written with this style, which we’ll refer to as “1970s-v1”.

the 1970s-v1 signature - Agatha consistent with her earlier years in style.

However, there are also impersonal letters (such as replies to fan mail or business correspondence) from her latter years that had a significantly different signature, which we’ll refer to as “1970s-v2”. In the 1970s-v2 signature the ‘g’ has a more normal shape with the loop to the left of the vertical downstroke. Either Agatha Christie changed her signature significantly in 1973-75 or perhaps her secretary signed on her behalf. The image below shows that it was graded by Beckett as authentic, but for us who actually signed it is unclear.

This is the 1970s_v2 signature - very different "g" and "r". It appears a couple of times in the mid 1970s.

Our readers who have insights on v1 and v2 should share them with us. Did Christie's signature really change this dramatically in her last few years of her life, or was someone else signing her correspondence? We already know from the penciled 'C' or 'M' examples above that someone else was prepping her letters in the 1970s.

The “r” in Christie:

This is another letter where the majority of signatures with provenance show a confident stroke from the bottom right foot of the ‘h’ moving directly to the top of the ‘r’ which follows the format of across then down (similar to Л). For most of her life the top of the Л was mostly non-existent (see examples in A-grade far below). In her latter years it became more pronounced and even contained a florid look (see directly below).

The double ‘l’ in Mallowan:

As with most letters that could be looped, Christie almost always looped them moving in at anti-clockwise motion before down-stroking the vertical part of the letter.

A good example of the "ll" and the "w" connecting to the "a" in a late life A-grade signature.

The ‘t’ in Agatha and Christie:

As mentioned in the norms, Christie have a fluid style that connected most letters together. The pen rarely left the paper while writing ‘Agatha’ or ‘Christie’, but always did to cross the ‘t’. In most cases, that horizontal line of the ‘t’ would fall to the right of the ‘h’ in Agatha.

The "t" cross well to the right of "h"

By studying signatures and the typical characteristics of the letters a collector can determine their confidence in its authenticity.


Regardless of the provenance or stated authenticity, all buyers should do their own due diligence. An experienced collector can often assess the item for sale, the vendor, any documentation accompanying it, the norms and the signature characteristics. In aggregate the collector can then make their own determination as to whether they view the signature as authentic.

In our opinion, it is appropriate to grade a signature as A, B, C or D (details below). Since one can no longer obtain an item directly from Agatha Christie, rarely ever can a signature be guaranteed 100% genuine. There can always be some level of doubt. Considering a signature to be fake as a starting point, and then seeking to reduce that doubt is often a better strategy than approaching one as authentic at first. Buyers often have rose-coloured glasses when it comes to their own collection or items they wish to add to them so being skeptical at first is prudent.

Under our grading system, consider the following:


An A-grade signature is one that has the majority of the following: very detailed provenance, is being sold by a knowledgeable and trusted vendor, is on Christie's personal stationary, has supporting materials or is part of a detailed letter, meets the norms for its type and has characteristics consistent with other period-correct items.

A-grade: A letter from the Callow collection. Perfect provenance.

An example would be the pending auction of correspondence between Agatha Christie and Elizabeth Callow, a long-time friend (image above). The auction comprises numerous letters, personal photographs, and the original envelopes posted by Christie. They are being sold by Callow’s family and by an respected auction house.

A couple of other A-grade examples are shown below.

A-grade: An association copy with provenance.

A-grade: Personal letter to Billy Wilder, sold by Heritage Auctions.


A B-grade signature is one that lacks provenance, but has many of the following attributes: an association copy, stated authenticity from a trusted vendor or auction house, and/or meets all the norms and characteristics expected. The examples below were association copies, were being sold by reputable dealers and had all the correct features.

B-grade: An association copy with all the correct norms & characteristics, sold by a trusted dealer.

B-Grade: An association copy, sold by a reputable dealer, with correct norms for a Westmacott signature.


A C-grade signature has many of the correct norms and characteristics, but lacks any sense of provenance or stated authenticity from a reliable source. It may have one or two atypical characteristics that start to cause doubts.

C-grade: "Agatha" and the slash look atypical, overall lacks confidence.

C-grade: Correct norms and characteristics, but no supporting information.

C-grade: "r" is flawed, 'i' to 's' connector is wrong, slash has hash mark


A D-grade signature will have many of the following: no provenance or association, is not being sold by a known dealer or auction house, has no stated authenticity from a reliable source and has many norms or characteristics that are atypical. The examples below all demonstrate numerous abnormalities.

D-grade: Everything is wrong here - no norms or usual characteristics

D-grade: No confidence, wrong 'g', no flow, slowly written.

D-grade: extra 'r' (Chrr..), odd last 'a' in Agatha, big gap from 'i' to 's', slash line lacks confidence.

D-grade: atypical 't' crossings, odd "Ch".

D-grade: Wrong "g", no connector from "i" to "s", nor "w" to "a"


Ascribing value to a signed item is very difficult as many factors affect it. Signed items that are associated with people important to Agatha Christie would certainly be more valuable than flat signatures. Period correct (i.e. books signed and dated in alignment with publication) and more vintage signatures would also be more valuable. Lastly, under our grading levels, an A-grade signature would command significantly more value than a D-grade signature. In general sale prices have demonstrated that a B-grade signature adds approximately £500 - £1,000 to the price of a book. For A-grade signatures the uniqueness of the item and the supporting documentation would drive the pricing. For C-grade and D-grade signatures, values may not always align with prices realized. A later resale of a lesser grade item may disappoint the vendor. Expect technology and education collectively to make awareness of questionable items greater as the years go by.


Hopefully this overview has provided some insights that will aid collectors. Start by seeking provenance, then stated authenticity, followed by your own assessment of norms and characteristics. You should then be able to decide whether you grade the item as A, B, C or D, from which you can decide how valuable it is to you and the price you would be willing to pay for it.

We strongly welcome opinions, input and further insights from our readers in what can quickly become a hotly debated and contentious topic.

Lastly... The signature in the Akhnaton book at the beginning of our article. Since the book was published in 1973, Agatha Christie would have signed this aged 82 or older. As discussed earlier, by then her signature was changing. This signature also has some atypical characteristics. In our opinion the 's' is unusual and not connected to other letters, the slash is not consistent, and the signature is too bold for her age. Consequently, we'd assign a D-grade.

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