M4 Enigma machine for German naval use. A German Naval 4-rotor Enigma enciphering machine (M4).  Made by Heimsoeth and Rinke, Berlin, 1943.

This lot has been removed from the website, please contact customer services for more information

Lot 291
M4 Enigma machine for German naval use.
A German Naval 4-rotor Enigma enciphering machine (M4).
Made by Olympia Buromaschinenwerke AG, Erfurt, Germany, 1944.

Sold for US$ 444,500 inc. premium
M4 Enigma machine for German naval use.
A German Naval 4-rotor Enigma enciphering machine (M4). Made by Olympia Buromaschinenwerke AG, Erfurt, Germany, 1944. Operational M4 Enigma machine, for exclusive German Naval use, with ID tag serial number M18196 and matching serial numbers on the base of the machine under the rotors, and on the lock, and with aluminum rotors I, VIII (marked M18196) and rotor VII (marked M16430), and Beta rotor and reflector, lamp-board display, standard QWERTY keyboard of 26 keys, white on black, battery switch, ebonite steckerbrett (plugboard), with 10 cables, the case lid with 2 spare cables, a contrast screen (modern replacement), original pasted typed instructions in German on to the inside of the lid, partially torn with loss, and a set of 10 spare bulbs, inner front panel with ink stamp "Klappe schliessen" , the inside of the lid additional stamped, the keyboard and rotors set in a black crackle finish metal case. Slight oxidation of metal hinges on front panel. Mounted in its original dark stained oak outer case, with metal lock and carrying handle, 345 x 285 x 165mm, (13¾ x 11 x 6¼ inches.); together with the original battery for the M4 (now defunct), and a file of colored photocopies of coded sheets from a file copy brought up from a sunken U- Boat.
WITH the special envelope contained the Hydra key, lettered, Spruchschlusseltafel fur den Wetterkurzschlussel (3. Auflage), numbered 653, dated April 1945, 110 x 160mm. Laminated; and 3 laminated enigma code recording sheets from an original file brought up from a sunken U-Boat. This lot has an accompanying condition report by Enigma Museum, Vermont, who looked over and cleaned this machine in October 2018.

The hydra key envelope held the start code needed to start up the an enigma machine, and inside the envelope was or is the small piece of paper with numbers that would be put into the machine to begin its operation. Of course this piece of paper is water soluble.
The story of the German Enigma machine starts in WWI, when the British were intercepting and reading all the German Navy signals, which gave them a significant advantage at sea throughout the War. The Enigma machine was designed and patented by Arthur Scherbius in 1918, but it was not until 1926 that the code-breaking of the WWI naval signals by the Western Allies was discovered by the German High Command. The Enigma was then chosen as the German enciphering machine for the military. The early enigmas had 3 interchangeable rotors (M3), which scrambled plain-text messages to produce a cipher text message, which was then sent via Morse code to a receiver machine with the same settings. The breaking of the Enigma codes by the Allies was one of the most important breakthroughs of World War II, and is regarded as shortening the war by at least 2 years. It started when Polish cryptographers passed on to the British their research on the codes in 1937, and in 1939 the French captured a German submarine with a codebook, while other information was retrieved by a spy in Germany. The outcome of this was that the 3 rotor code was broken early on in the war by the code breakers at Bletchley Park set up in 1937, including Turing, Foss, Knox and many others. When the M4 came into use on February 1942, it took over 9 months for Bletchley to crack that code, assisted by the capture of codebooks from U-599 in October 1942. Various other devices were added to the M4 from 1944 to complicate the messages, notably a UKW-D, a field rewireable refractor to replace the reflector and extra wheel.

The M4 was ordered to be built in late 1941, by Admiral Doenitz, for use in his U-boat forces, as he rightly suspected that the security of the M3 had been compromised by the capture of U-570 in August 1941. It would have been in use on U-boats, U-boat support ships, and shore installations supporting U-boat operations. This example is believed to have been from a U-Boat Communications Base in Scandinavia, and was obviously from a communications base rather than a submarine due to its fine condition (little corrosion, and the fact that the rotors have different machine codes on them suggesting that it was part of an Enigma machine pool. The need for a safe secure communications system was paramount for the success of the U-Boat campaign in the Atlantic. For this campaign, the German Naval High Command needed to know, on a daily basis, the positions of the U-Boats, and the vessels needed to receive orders as to where they were to go, and all this information had to be secure.

The numbers of surviving M4s both from surviving U-Boats (c.140 captured out of 800 built), and from the shore bases along the Atlantic coasts, 4 bases Bergen, Kiel, Wilhelmshaven and La Rochelle, given that at least 90% of commanders would have destroyed their U-Boat machines before surrendering, and that the machines, between 30 and 40 machines in each base, located at shore communication bases had similar instructions, CAN BE ESTIMATED AT A MAXIMUM OF PERHAPS 100 EXAMPLES EXTANT, mostly now languishing in Government storerooms around the world. The M4s, all came directly into the hands of the Allied Naval Forces after the war, whether it be in Britain, France, Australia, US, Denmark or Holland, and were not allowed to slip out of military control. The US/British forces rounded up as many M3 (army) machines as they could from the surrendering German Forces in mainland Europe, and many of them were sold back to the Eastern Bloc on a clandestine basis, which allowed the Allies to listen in to military orders throughout the Cold War. Churchill himself made a speech in summer 1945, when he said that the enigma machines had all been destroyed!
Of the surviving M4s it is suspected that for every 10 M3s there might be one M4. Analysis of the 24 Museums around the world that exhibit Enigma machines, show a total of about 50 Enigma machines on display, of which just 7 are M4s. The remainder are M3s, with the occasional late war M6 or M7. Of surviving U-Boats on display in museums around the world, there are just 4 examples out of 800 or more built. The Enigma M4 machine is justly deemed to be the rarest of all Enigma machines.
M4 Enigma machine for German naval use. A German Naval 4-rotor Enigma enciphering machine (M4).  Made by Heimsoeth and Rinke, Berlin, 1943.
M4 Enigma machine for German naval use. A German Naval 4-rotor Enigma enciphering machine (M4).  Made by Heimsoeth and Rinke, Berlin, 1943.
Auction information

This auction is now finished. If you are interested in consigning in future auctions, please contact the specialist department. If you have queries about lots purchased in this auction, please contact customer services.

Buyers' Obligations


If you have any complaints or questions about the Conditions of Sale, please contact your nearest customer services team.

Buyers' Premium and Charges

For all Sales categories excluding Arms & Armour, Coins and Medals, Motor Cars, Motorcycles, Wine & Whisky

27.5% on the first $25,000 of the hammer price;
26% of the hammer price of amounts in excess of $25,000 up to and including $1,000,000;
20% of the hammer price of amounts in excess of $1,000,000 up to and including $6,000,000;
and 14.5% of the hammer price of any amounts in excess of $6,000,000.

Payment Notices

Payment for purchases may be made in or by (a) cash, (b) cashier's check or money order, (c) personal check with approved credit drawn on a U.S. bank, (d) wire transfer or other immediate bank transfer, or (e) Visa, MasterCard, American Express or Discover credit, charge or debit card for returning clients only. Please note that the amount of cash notes and cash equivalents that can be accepted from a given purchaser may be limited.

Shipping Notices

If you have requested a shipping quote, we will send this to you via email within 5 business days of the auction ending.

Please note our shipping quotes are bespoke and require special care and handling from our team and shippers. Shipping will be booked after payment is received. Please allow 7-14 business days from the time of booking for packing and dispatch, depending on your chosen shipping method. If your purchase is time sensitive, or you wish to explore other options, please see our list of alternative third party shippers in New York and Los Angeles who may be able to assist you.

If you have any questions, please contact our Client Services team.