HF Recommendation 
LEGIC advant
For secure access control and multi-application solutions.
Security 3DES / AES
Memory 4 KB
LEGIC prime: Technical Data, Security and Use
LEGIC prime is an older HF RFID product family from LEGIC Identsystems for contactless identification media at 13.56 MHz. The two current legacy types MIM256-MN and MIM1024-MN use the proprietary radio protocol LEGIC RF. The nominal memory is 256 and 1,024 bytes respectively, of which, according to the current LEGIC product overview, 234 and 1,002 bytes respectively are available for applications.
Today, LEGIC prime is mainly relevant for existing installations. We therefore offer the chip mainly for existing LEGIC access control systems. LEGIC itself now classifies MIM256-MN and MIM1024-MN as “legacy”. For new systems with higher security requirements, LEGIC advant is the more suitable option within the LEGIC ecosystem.
| Feature | Value |
|---|---|
| Manufacturer | LEGIC Identsystems AG |
| Product family | LEGIC prime |
| Type designation | MIM256-MN / MIM1024-MN |
| RFID class | HF |
| Frequency | 13.56 MHz |
| RF standard | LEGIC RF, proprietary |
| Data rate | Up to 12.5 kbit/s |
| EEPROM / total memory | 256 / 1,024 bytes |
| User memory | 234 / 1,002 bytes |
| Memory structure | Variable segment lengths, up to 32 / 127 applications |
| Authentication / authorization | Proprietary LEGIC method, MTSC |
| Data transmission | Proprietary protection method |
| Data storage | Proprietary protection method |
| Key and rights management | Master-Token System-Control (MTSC) |
| UID | 4 bytes, write-protected on the original transponder |
| Read range | Up to 20 cm according to LEGIC, depending on reader and medium |
| Smartphone NFC | Not directly readable as a normal NFC tag |
| Product status at LEGIC | Legacy |
| Typical media | RFID card, key fob, key and other identification media |
| Security rating | Legacy |
| Recommendation | Mainly for existing LEGIC prime installations |
LEGIC now lists MIM256-MN and MIM1024-MN as legacy smart card ICs. The two variants operate via LEGIC RF at up to 12.5 kbit/s and offer 234 and 1,002 bytes of usable memory respectively.
Typical Applications
LEGIC prime was developed for multi-application media. For its smart card ICs, LEGIC mainly names access control, time recording and cashless payment. The earlier prime data sheet additionally lists ticketing, parking and electronic purses.
Typical applications are:
- Access control in existing LEGIC systems
- Time recording
- Employee and multi-application ID cards
- Closed-loop payment and canteen applications
- Ticketing and parking systems in existing installations
- Combination of several applications on one data carrier
Primarily RFID cards and RFID key fobs are suitable as media. Before reordering, it should be checked whether the existing system expects MIM256-MN or MIM1024-MN and how the applications are segmented on the data carrier.
Security
Security level: Legacy
LEGIC prime uses proprietary methods for data transmission, memory access and rights management. However, the system does not offer modern cryptographic card authentication.
Security analyses showed that cards can be read out and emulated and that protection mechanisms can be bypassed. LEGIC prime may still be required for existing installations. For new applications with higher security requirements, a current chip generation such as LEGIC advant should be considered.
Advantages and Disadvantages of LEGIC prime
| Advantages | Disadvantages |
|---|---|
| Still relevant for existing LEGIC prime systems | Proprietary security mechanism without modern key-based card authentication |
| Variable memory segmentation for multiple applications | Security mechanisms have been bypassed in practice |
| Up to 32 or 127 applications | No direct reading via normal smartphone NFC |
| Current LEGIC reader generations still support prime | LEGIC now lists MIM256-MN and MIM1024-MN only as legacy |
| Up to 1,002 bytes of usable memory on the MIM1024 | Data rate limited to a maximum of 12.5 kbit/s |
Alternatives to LEGIC prime
Depending on the existing reader infrastructure, security requirements and desired smartphone use, other chip types may be better suited.
HF / NFC Recommendation 
MIFARE DESFire EV3
For secure company ID cards and multi-application cards.
Security AES-128
Memory 2 / 4 / 8 / 16 KB
HF / NFC Recommendation 
NTAG 213 / 215 / 216
For NFC marketing, business cards and smartphone applications.
Security PWD
Memory 144–888 B
Frequently Asked Questions about LEGIC prime
How much memory does LEGIC prime have?
LEGIC prime is available as MIM256-MN and MIM1024-MN. The older manufacturer data sheet specifies the two variants with 256 and 1,024 bytes of total memory respectively. The current LEGIC product page states 234 and 1,002 bytes respectively as the usable memory size. The difference results from reserved areas at the beginning of the memory. The technical analysis by Plötz and Nohl describes 22 reserved bytes before the actual payload area for segmented media.
Which variants of LEGIC prime are available?
LEGIC currently lists MIM256-MN and MIM1024-MN as legacy smart card ICs. MIM256 offers 234 bytes of application area and, according to the manufacturer, supports up to 32 applications. The MIM1024 offers 1,002 bytes, with up to 127 applications. Older technical studies also mention the MIM22, but it is no longer among the prime ICs listed by LEGIC today.
How secure is LEGIC prime?
For today's security-critical applications, LEGIC prime should be classified as a legacy technology. The system uses proprietary protection mechanisms, but no modern key-based card authentication. Security researchers showed that cards can be fully read out and emulated and that essential protective functions are enforced by official readers rather than by the transponder itself. This distinguishes prime from current systems with cryptographic authentication.
Can LEGIC prime be read with a smartphone?
Not directly with the normal NFC interface like an NFC tag. LEGIC prime uses the proprietary LEGIC RF method. Modern LEGIC readers can support prime smart cards and mobile credentials via NFC or Bluetooth in parallel. However, the smartphone does not read the LEGIC prime card. It uses a separate mobile credential solution, for example via the current LEGIC platform.
Which readers support LEGIC prime?
The reader must explicitly support LEGIC prime or LEGIC RF. The shared frequency of 13.56 MHz is not sufficient for compatibility. Current LEGIC security modules of the 4000 and 6000 series still list prime among the supported RFID technologies. For existing installations, the reader model, firmware, MTSC configuration and the transponder used so far should be checked before ordering new cards or other media.
What is the difference between LEGIC prime and LEGIC advant?
LEGIC prime uses the proprietary LEGIC RF protocol and, according to the current manufacturer overview, reaches a maximum of 12.5 kbit/s. LEGIC advant, on the other hand, comprises ICs with ISO/IEC 15693 or ISO/IEC 14443 A and newer security methods. The specific encryption depends on the respective advant IC. A direct replacement is therefore not possible simply because of the shared frequency. Readers, applications and authorization structure must support the new technology.
When does LEGIC prime still make sense today?
The most important use case is existing systems that explicitly expect MIM256-MN or MIM1024-MN. These include, for example, reorders of employee ID cards, access cards or other media in an existing LEGIC prime infrastructure. For a new system, a current chip generation should be considered, especially if protection against copying and manipulation is required.
Is LEGIC prime still being produced?
LEGIC describes MIM256-MN and MIM1024-MN as “legacy” on the current product page. At the same time, both types are still listed in the RoHS declaration of conformity LZ-01-001p, Edition 02.2026. However, LEGIC does not publish a clear production status such as “Active” there. It is therefore not possible to reliably determine from the public manufacturer documents to what extent new ICs are being produced. Availability should be checked for the specific project.
What is the read range of LEGIC prime?
LEGIC specifies a range of up to 20 cm for MIM256-MN and MIM1024-MN. This value is a manufacturer maximum and not a guaranteed range of a finished card or key fob. Reader antenna, transponder antenna, media format, installation and the environment influence the actual distance. For replacement media in an existing installation, the specific combination of transponder and reader should therefore be tested.
Technical sources
Data as of: September 2026
The technical information is based on the current product overview “LEGIC Smartcard ICs” from LEGIC Identsystems AG, in which MIM256-MN and MIM1024-MN are listed as legacy ICs with LEGIC RF, 234 and 1,002 bytes of memory respectively, a range of up to 20 cm and up to 12.5 kbit/s.
For the nominal memory sizes and the original product features, the LEGIC manufacturer document “LEGIC prime – Datenträger (MIM)”, document L1-01-002c-de, edition 02.2003, was also used. The current manufacturer status is supplemented by the RoHS Declaration LZ-01-001p, Edition 02.2026, dated 17 February 2026.
The security assessment is based on Henryk Plötz and Karsten Nohl, “Peeling Away Layers of an RFID Security System”, Financial Cryptography and Data Security 2011 and SAR-PR-2011-03 respectively. The statements on the distinction between prime smart cards and smartphone credentials are also based on the current LEGIC documentation on the 4000 and 6000 series.
Trademark notice
LEGIC® is a registered trademark of LEGIC Identsystems AG. LEGIC prime is a product name of LEGIC Identsystems AG.