Book C-4 Kernel Specification

© 2026 EMVCo, LLC. All rights reserved. Reproduction, distribution and other use of this document is permitted only pursuant to the applicable agreement between the user and EMVCo found at www.emvco.com. EMV ® is a registered trademark or trademark of EMVCo, LLC in the United States and other countries. EMV ® Contactless Specifications for Payment Systems Book C-4 Kernel 4 Specification Version 2.12 July 2026 EMV ® Contactless Specifications for Payment Systems Kernel 4 Specification v2.12 Page i / xi © 2026 EMVCo, LLC. All rights reserved. Reproduction, distribution and other use of this document is permitted only pursuant to the applicable agreement between the user and EMVCo found at www.emvco.com. EMV ® is a registered trademark or trademark of EMVCo, LLC in the United States and other countries. Legal Notice Unless the user has an applicable separate agreement with EMVCo or with the applicable payment system, any and all uses of these Specifications is subject to the terms and conditions of the EMVCo Terms of Use agreement available at www.emvco.com and the following supplemental terms and conditions. The license granted in the EMVCo Terms of Use specifically excludes (a) the right to disclose, distribute or publicly display these Specifications or otherwise make these Specifications available to any third party, and (b) the right to make, use, sell, offer for sale, or import any software or hardware that practices, in whole or in part, these Specifications. Further, EMVCo does not grant any right to use the Kernel Specifications to develop contactless payment applications designed for use on a Card (or components of such applications). As used in these supplemental terms and conditions, the term “Card” means a proximity integrated circuit card or other device containing an integrated circuit chip designed to facilitate contactless payment transactions. Additionally, a Card may include a contact interface and/or magnetic stripe used to facilitate payment transactions. To use the Specifications to develop contactless payment applications designed for use on a Card (or components of such applications), please contact the applicable payment system. To use the Specifications to develop or manufacture products, or in any other manner not provided in the EMVCo Terms of Use, please contact EMVCo. These Specifications are provided "AS IS" without warranties of any kind, and EMVCo neither assumes nor accepts any liability for any errors or omissions contained in these Specifications. EMVCO DISCLAIMS ALL REPRESENTATIONS AND WARRANTIES, EXPRESS OR IMPLIED, INCLUDING WITHOUT LIMITATION IMPLIED WARRANTIES OF MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE, TITLE AND NON - INFRINGEMENT, AS TO THESE SPECIFICATIONS. EMVCo makes no representations or warranties with respect to intellectual property rights of any third parties in or in relation to the Specifications. EMVCo undertakes no responsibility to determine whether any implementation of these Specifications may violate, infringe, or otherwise exercise the patent, copyright, trademark, trade secret, know-how, or other intellectual property rights of third parties, and thus any person who implements any part of these Specifications should consult an intellectual property attorney before any such implementation. Without limiting the foregoing, the Specifications may provide for the use of public key encryption and other technology, which may be the subject matter of patents in several countries. Any party seeking to implement these Specifications is solely responsible for determining whether its activities require a license to any such technology, including for patents on public key encryption technology. EMVCo shall not be liable under any theory for any party's infringement of any intellectual property rights in connection with these Specifications. EMV ® Contactless Specifications for Payment Systems Kernel 4 Specification v2.12 Page ii / xi © 2026 EMVCo, LLC. All rights reserved. Reproduction, distribution and other use of this document is permitted only pursuant to the applicable agreement between the user and EMVCo found at www.emvco.com. EMV ® is a registered trademark or trademark of EMVCo, LLC in the United States and other countries. Revision Log – Version 2.12 The following changes have been made to the document since the publication of Version 2.11. Some of the numbering and cross references in this version have been updated to reflect changes introduced by the published bulletins. The numbering of existing requirements did not change, unless explicitly stated otherwise. Incorporated changes described in the following Specification Updates: • SB324 Updates to EMV Contactless Book C-4 Kernel 4 Specification. Other editorial changes: • None EMV ® Contactless Specifications for Payment Systems Kernel 4 Specification v2.12 Page iii / xi © 2026 EMVCo, LLC. All rights reserved. Reproduction, distribution and other use of this document is permitted only pursuant to the applicable agreement between the user and EMVCo found at www.emvco.com. EMV ® is a registered trademark or trademark of EMVCo, LLC in the United States and other countries. Contents Legal Notice ...................................................................................................................... i Revision Log – Version 2.12 ............................................................................................ ii Contents .......................................................................................................................... iii Figures ............................................................................................................................ vii Tables ............................................................................................................................ viii Requirements .................................................................................................................. ix 1 Introduction ................................................................................................................ 1 1.1 Scope .................................................................................................................. 1 1.2 Audience ............................................................................................................. 1 1.3 Volumes of Contactless Specification .................................................................. 1 1.4 Reference Material .............................................................................................. 2 1.5 Notational Conventions ....................................................................................... 4 1.5.1 Use of Terms ........................................................................................... 4 1.5.2 Reserved for Future Use (RFU) ............................................................... 4 1.6 mPOS Architectures ............................................................................................ 5 1.7 Overview ............................................................................................................. 7 2 Contactless EMV Mode and Transaction Flows ....................................................... 9 2.1 Contactless EMV Mode of Operation ................................................................... 9 2.1.1 Transaction support for Contactless EMV Mode ...................................... 9 2.1.2 [Section removed] .................................................................................. 10 2.1.3 [Section removed] .................................................................................. 10 2.1.4 Contactless EMV Mode Transactions .................................................... 10 2.1.5 Contactless Mobile Transaction ............................................................. 10 2.2 Contactless Transaction Processing .................................................................. 11 2.2.1 Premature card removal ......................................................................... 12 2.2.2 Offline Transaction ................................................................................. 14 2.2.3 Partial Online Transaction ...................................................................... 14 2.2.4 Delayed Authorisation ............................................................................ 15 2.3 Contactless Transaction Configurations ............................................................ 16 3 Processing Overview ............................................................................................... 20 4 Initiate Application Processing ............................................................................... 21 4.1 Overview ........................................................................................................... 21 4.2 Commands ........................................................................................................ 21 4.3 Processing Requirements.................................................................................. 22 EMV ® Contactless Specifications for Payment Systems Kernel 4 Specification v2.12 Page iv / xi © 2026 EMVCo, LLC. All rights reserved. Reproduction, distribution and other use of this document is permitted only pursuant to the applicable agreement between the user and EMVCo found at www.emvco.com. EMV ® is a registered trademark or trademark of EMVCo, LLC in the United States and other countries. 4.3.1 Pre-PDOL Processing ............................................................................ 22 4.3.2 PDOL Processing .................................................................................. 23 4.3.3 Terminal Type – Modified ....................................................................... 24 4.3.4 Enhanced Contactless Reader Capabilities ........................................... 27 4.3.5 Terminal Type ........................................................................................ 29 4.3.6 GPO Response Check ........................................................................... 29 4.3.7 Determination of Transaction support for EMV Mode ............................. 30 4.3.8 Determination of Transaction Support for Contactless Mobile ................ 31 5 Read Application Data ............................................................................................. 32 5.1 Overview ........................................................................................................... 32 5.2 Commands ........................................................................................................ 32 5.3 Processing Requirements.................................................................................. 32 5.4 [Section Removed] ............................................................................................ 36 6 Offline Data Authentication ..................................................................................... 37 6.1 Overview ........................................................................................................... 37 6.2 Processing Requirements.................................................................................. 37 6.2.1 Offline Data Authentication not performed ............................................. 37 6.2.2 Single ODA Method Supported .............................................................. 38 6.2.3 [Section Removed] ................................................................................. 38 6.2.4 Scheme Certification Authority Public Keys............................................ 38 6.2.5 [Section Removed] ................................................................................. 39 6.2.6 Combined Dynamic Data Authentication / AC Generation ...................... 39 7 Processing Restrictions .......................................................................................... 40 7.1 Overview ........................................................................................................... 40 7.2 Processing Requirements.................................................................................. 40 7.2.1 [Section removed] .................................................................................. 41 7.2.2 EMV Processing Restrictions ................................................................. 42 7.2.3 Supplementary Processing Restrictions ................................................. 46 7.2.4 [Section removed] .................................................................................. 48 8 Cardholder Verification ............................................................................................ 49 8.1 Overview ........................................................................................................... 49 8.2 Processing Requirements.................................................................................. 49 8.2.1 Process Control ..................................................................................... 49 8.2.2 CVM Processing .................................................................................... 50 8.2.3 CVM List Processing .............................................................................. 52 8.2.4 Contactless Mobile CVM Processing ..................................................... 56 8.2.5 Cardholder Verification Unable To Complete over Contactless Interface 61 8.2.6 Reader CVM Required Limit Exceeded Indicator Not Set ...................... 66 EMV ® Contactless Specifications for Payment Systems Kernel 4 Specification v2.12 Page v / xi © 2026 EMVCo, LLC. 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EMV ® is a registered trademark or trademark of EMVCo, LLC in the United States and other countries. 9 Terminal Risk Management ..................................................................................... 76 9.1 Overview ........................................................................................................... 76 9.2 Processing Requirements.................................................................................. 77 9.2.1 Floor Limit Checking .............................................................................. 77 9.2.2 Random Transaction Selection .............................................................. 77 9.2.3 Velocity Checking .................................................................................. 77 9.2.4 Exception File Checking ......................................................................... 78 10 1 st Terminal Action Analysis .................................................................................... 79 10.1 Overview ........................................................................................................... 79 10.2 Processing Requirements.................................................................................. 80 10.2.1 Offline Processing Results ..................................................................... 80 10.2.2 Zero Amount Allowed and Status Check Requested Validation ............. 88 10.2.3 [Section removed] .................................................................................. 89 10.2.4 Request AC in First GENERATE AC ...................................................... 90 11 1 st Card Action Analysis .......................................................................................... 91 11.1 Overview ........................................................................................................... 91 11.2 Processing Requirements.................................................................................. 92 11.2.1 Format of the Response to GENERATE AC Command ......................... 92 11.2.2 General Card Action Analysis ................................................................ 96 11.2.3 Card Returns SW = '6984' ...................................................................... 97 11.2.4 Card Returns a TC ............................................................................... 100 11.2.5 Card Returns an AAC .......................................................................... 102 11.2.6 Card Returns an ARQC ....................................................................... 102 12 Online Processing .................................................................................................. 107 12.1 Overview ......................................................................................................... 107 12.2 Processing Requirements................................................................................ 108 12.2.1 [Section removed] ................................................................................ 108 12.2.2 Partial Online Processing ..................................................................... 109 12.2.3 Delayed Authorisation Processing (Not applicable to mPOS-C, mPOS-CSP) ............................................................................................................ 113 13 Transaction Completion ........................................................................................ 114 13.1 Overview ......................................................................................................... 114 13.2 Transaction Approved ..................................................................................... 114 13.3 Transaction Declined ....................................................................................... 116 14 Membership-Related Data Processing ................................................................. 117 14.1 Overview ......................................................................................................... 117 14.2 Data ................................................................................................................ 117 EMV ® Contactless Specifications for Payment Systems Kernel 4 Specification v2.12 Page vi / xi © 2026 EMVCo, LLC. 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EMV ® is a registered trademark or trademark of EMVCo, LLC in the United States and other countries. 14.3 Processing Requirements................................................................................ 118 Annex A Kernel 4 Data Elements ..................................................................... 119 A.1 Data Elements ................................................................................................. 120 A.2 Transaction Data ............................................................................................. 138 A.3 Read Record Data ........................................................................................... 139 A.4 Data Records and Discretionary Data.............................................................. 140 Annex B Configuration Data ............................................................................. 141 B.1 Configuration Data Provided by the Terminal .................................................. 141 B.2 Configuration Data Provided by Entry Point ..................................................... 143 Annex C mPOS Requirements ......................................................................... 144 Annex D Glossary ............................................................................................. 146 EMV ® Contactless Specifications for Payment Systems Kernel 4 Specification v2.12 Page vii / xi © 2026 EMVCo, LLC. All rights reserved. Reproduction, distribution and other use of this document is permitted only pursuant to the applicable agreement between the user and EMVCo found at www.emvco.com. EMV ® is a registered trademark or trademark of EMVCo, LLC in the United States and other countries. Figures Figure 2-1: Transaction Flow Overview ............................................................................ 12 Figure 8-1: Process Control ............................................................................................. 49 Figure 8-2: CVM Processing ............................................................................................ 51 Figure 8-3: Contactless Mobile CVM Processing ............................................................. 55 Figure 8-4: Cardholder Verification Unable To Complete ................................................. 61 Figure 8-5: Contactless Mobile CVM Result Validation .................................................... 66 Figure 8-6: Card Handling Reader CVM Required Limit Exceeded Indicator Not Set ....... 73 EMV ® Contactless Specifications for Payment Systems Kernel 4 Specification v2.12 Page viii / xi © 2026 EMVCo, LLC. All rights reserved. Reproduction, distribution and other use of this document is permitted only pursuant to the applicable agreement between the user and EMVCo found at www.emvco.com. EMV ® is a registered trademark or trademark of EMVCo, LLC in the United States and other countries. Tables Table 1-1: Terminal and mPOS Architectures .................................................................... 5 Table 2-1: Contactless Mode Selection .............................................................................. 9 Table 2-2: Contactless Transaction Combinations ........................................................... 16 Table 2-3: Reader Configurations .................................................................................... 17 Table 4-1: Terminal Type – EMV Tag '9F35' .................................................................... 24 Table 4-2: Contactless Reader Capabilities – Tag '9F6D' ................................................ 25 Table 4-3: Terminal Type – Modified ................................................................................ 26 Table 4-4: Enhanced Contactless Reader Capabilities - Tag ‘9F6E’ ................................ 27 Table 5-1: Card Interface and Payment Capabilities – Tag '9F70' .................................... 33 Table 5-2: Application Interchange Profile (AIP) ............................................................... 35 Table 7-1: Bit Settings for Application Usage Control (AUC) ............................................ 44 Table 8-1: Mobile CVM Results – Tag '9F71' ................................................................... 56 Table 8-2: Final Outcome Parameter Settings.................................................................. 68 Table 10-1: Terminal Verification Results (TVR) Settings ................................................. 80 Table 10-2: Reader Configurations IAC/TAC Checks ....................................................... 82 Table 11-1: Card Action analysis - Final Outcome Parameter Settings for Try Another Interface ........................................................................................................ 93 Table 11-2: Card Action analysis - Final Outcome Parameter Settings for End Application94 Table 11-3: Card returns SW=’6984’ – Try Again Parameter Settings .............................. 98 Table 11-4: Card returns SW=’6984’ – End Application Parameter Settings .................... 99 Table 12-1: Partial Online - Parameter Settings ............................................................. 110 Table 12-2: Authorisation Response Code (ARC) Values .............................................. 110 Table 12-3: Request Online PIN - Parameter Settings ................................................... 111 Table 14-1: Data Elements............................................................................................. 120 Table 14-2: Transaction Data ......................................................................................... 138 Table 14-3: Mandatory Read Record Data Objects ........................................................ 139 Table 14-4: Data Record for EMV Mode (Minimum Data Elements) ............................... 140 Table 14-5: Kernel Configuration Data ........................................................................... 141 Table 14-6: Entry Point Configuration Data .................................................................... 143 EMV ® Contactless Specifications for Payment Systems Kernel 4 Specification v2.12 Page ix / xi © 2026 EMVCo, LLC. All rights reserved. Reproduction, distribution and other use of this document is permitted only pursuant to the applicable agreement between the user and EMVCo found at www.emvco.com. EMV ® is a registered trademark or trademark of EMVCo, LLC in the United States and other countries. Requirements Requirements – Card Early Removal ............................................................................... 13 Requirements – Offline Transaction ................................................................................. 14 Requirements – Partial Online Transaction ...................................................................... 14 Requirements – Partial Online Transaction Completion ................................................... 14 Requirements – Delayed Authorisation ............................................................................ 15 Requirements – Transaction Combinations ...................................................................... 19 Requirements – GET PROCESSING OPTIONS .............................................................. 21 Requirements – Pre-PDOL Processing ............................................................................ 23 Requirements – GPO Without PDOL Data ....................................................................... 23 Requirements – PDOL Data in GPO ................................................................................ 23 Requirements – GPO Includes Modified Terminal Type ................................................... 26 Requirements – GPO Includes Enhanced Contactless Reader Capabilities ..................... 29 Requirements – GPO Includes (unmodified) Terminal Type ............................................. 29 Requirements – GPO Response Check ........................................................................... 29 Requirements – Transaction support for Contactless EMV Mode .................................... 30 Requirements – Determination of Transaction Support for Contactless Mobile ................ 31 Requirements – READ RECORDs ................................................................................... 34 Requirements – Offline Data Authentication ..................................................................... 37 Requirements - Offline Data Authentication not performed .............................................. 38 Requirements – Offline Data Authentication When Card Supports a Single Method ........ 38 Requirements – [Requirement Removed] ........................................................................ 38 Requirements – Offline Data Authentication Keys ............................................................ 39 Requirements – [Requirement Removed] ........................................................................ 39 Requirements – Combined Dynamic Offline Data Authentication ..................................... 39 Requirements – Processing Restrictions: Application Version Number ........................... 42 Requirements – Processing Restrictions: AUC Domestic ................................................ 43 Requirements – Processing Restrictions: AUC International ........................................... 43 Requirements – Processing Restrictions: AUC Environment for an ATM ........................ 44 Requirements – Processing Restrictions: AUC Environment for other than an ATM ....... 44 Requirements – Processing Restrictions: Dates .............................................................. 45 EMV ® Contactless Specifications for Payment Systems Kernel 4 Specification v2.12 Page x / xi © 2026 EMVCo, LLC. 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Requirements – Supplementary Processing Restrictions: Domestic Delayed Authorisation46 Requirements – Supplementary Processing Restrictions: International Delayed Authorisation .......................................................................................... 47 Requirements – Cardholder Verification Processing ........................................................ 50 Requirements – Card Supports Cardholder Verification but CVM List Not Present .......... 52 Requirements – Reader CVM Supported Methods .......................................................... 52 Requirements – CVM List Processing .............................................................................. 53 Requirements – Online PIN.............................................................................................. 54 Requirements – Contactless Mobile CVM Processing ...................................................... 58 Requirements – Cardholder Verification Unable To Continue over Contactless Interface 63 Requirements – Contactless Mobile CVM Result Validation............................................. 68 Requirements – CVM Processing – Card Supports Cardholder Verification but CVM List Not Present or Empty ................................................................................... 74 Requirements – CVM Processing – Card Supports Cardholder Verification and CVM List contains ‘No CVM Required’ .................................................................. 74 Requirements – CVM Processing – Card Supports Cardholder Verification and CVM list is present but does not contain ‘No CVM Required’ ................................... 75 Requirements – CVM Processing – Card Does Not Support Cardholder Verification ....... 75 Requirements – Terminal Risk Management Not Requested By Card ............................. 76 Requirements – Terminal Risk Management Requested By Card .................................... 76 Requirements – Terminal Risk Management – Floor Limit Checking ............................... 77 Requirements – Terminal Risk Management – Exception File Checking .......................... 78 Requirements – Terminal Action Analysis – Offline Only Compare Denial Codes ............ 83 Requirements – Terminal Action Analysis – Online Only Compare Denial Codes ............ 83 Requirements – Terminal Action Analysis – Online Only Terminal Unable To Go Online . 84 Requirements – Terminal Action Analysis – Offline with Online Capability Compare Denial Codes .................................................................................................... 84 Requirements – Terminal Action Analysis – Offline with Online Capability Terminal Compare Online Codes ......................................................................................... 85 Requirements – Terminal Action Analysis – Offline with Online Capability Terminal Unable To Go Online .......................................................................................... 86 Requirements – Terminal Action Analysis – Delayed Authorisation Terminal Compare Denial Codes .................................................................................................... 87 Requirements – Terminal Action Analysis – Delayed Authorisation Terminal Compare Online Codes .................................................................................................... 87 EMV ® Contactless Specifications for Payment Systems Kernel 4 Specification v2.12 Page xi / xi © 2026 EMVCo, LLC. 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Requirements – Zero Amount Allowed ............................................................................. 88 Requirements – Status Check Requested ........................................................................ 88 Requirements – Card Action Analysis Return Formats ..................................................... 95 Requirements – Card Action Analysis Processing ............................................................ 96 Requirements – Card returns SW=’6984’ and transaction has not been restarted ........... 99 Requirements – Card returns SW=’6984’ and transaction has been restarted ................. 99 Requirements – Card Action Analysis Return TC ........................................................... 101 Requirements – Card Action Analysis Return AAC ........................................................ 102 Requirements – Card Action Analysis Return ARQC – CDA failure ............................... 103 Requirements – Card Action Analysis Return ARQC – Offline Only Terminal ................ 104 Requirements – Card Action Analysis Return ARQC – EMV Mode (partial online) at Online Capable Terminal ................................................................................. 105 Requirements – Card Action Analysis Return ARQC – EMV Mode (partial online) at Delayed Authorisations Terminal ........................................................................ 106 Requirements – Online Processing ................................................................................ 107 Requirements – Online Response Processing ............................................................... 111 Requirements – Online Response Processing ............................................................... 112 Requirements – Delayed Authorisation Processing ........................................................ 113 Requirements – Membership-Related Data ................................................................... 118 EMV ® Contactless Specifications for Payment Systems Kernel 4 Specification v2.12 Page 1 / 151 © 2026 EMVCo, LLC. 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EMV ® is a registered trademark or trademark of EMVCo, LLC in the United States and other countries. 1 Introduction Kernel 4 is a contactless Reader kernel designed for interoperability with a suitable contactless payment application including American Express Contactless Payment Products. 1.1 Scope This document, the EMV Contactless Specifications for Payment Systems, Kernel 4 Specification, defines the mandatory and optional functionality required when implementing Kernel 4. 1.2 Audience This specification is intended for use by system designers in payment systems and financial institution staff responsible for implementing financial applications. 1.3 Volumes of Contactless Specification This specification is part of an eleven-volume set: Book A: Architecture and General Requirements Book B: Entry Point Specification Book C-2: Kernel 2 Specification Book C-3: Kernel 3 Specification Book C-4: Kernel 4 Specification Book C-5: Kernel 5 Specification Book C-6: Kernel 6 Specification Book C-7: Kernel 7 Specification Book C-8: Kernel 8 Specification Book E: Security and Key Management EMV Level 1 Specifications for Payment Systems – EMV Contactless Interface Specification EMV ® Contactless Specifications for Payment Systems Kernel 4 Specification v2.12 Page 2 / 151 © 2026 EMVCo, LLC. All rights reserved. Reproduction, distribution and other use of this document is permitted only pursuant to the applicable agreement between the user and EMVCo found at www.emvco.com. EMV ® is a registered trademark or trademark of EMVCo, LLC in the United States and other countries. 1.4 Reference Material The following standards contain provisions that are referenced in this specification. The latest version including all published amendments shall apply unless a publication date is explicitly stated. If any provision or definition in this specification differs from those in the listed specifications and standards, the provision or definition herein shall take precedence. Reference Publication Name [EMV 4.4] EMV ® Integrated Circuit Card Specifications for Payment Systems, Version 4.4, October 2022, including: [EMV 4.4 Book 1] EMV Integrated Circuit Card Specifications for Payment Systems, Book 1, Application Independent ICC to Terminal Interface Requirements [EMV 4.4 Book 2] EMV Integrated Circuit Card Specifications for Payment Systems, Book 2, Security and Key Management [EMV 4.4 Book 3] EMV Integrated Circuit Card Specifications for Payment Systems, Book 3, Application Specification [EMV 4.4 Book 4] EMV Integrated Circuit Card Specifications for Payment Systems, Book 4, Cardholder, Attendant, and Acquirer Interface Requirements [PTOKS2.0] EMV Payment Tokenisation Specification Technical Framework, v2.0 [ISO 3166] Codes for the representation of names of countries and their subdivisions [ISO 4217] Codes for the representation of currencies and funds [ISO 7813] Identification cards – Financial transaction cards [ISO 7816-5] Identification cards – Integrated circuit cards – Part 5: Registration of application providers [ISO 7816-4] Identification cards – Integrated circuit cards – Part 4: Organization, security and commands for interchange [ISO 8583] Bank card originated messages – Interchange message specifications – Content for financial transactions EMV ® Contactless Specifications for Payment Systems Kernel 4 Specification v2.12 Page 3 / 151 © 2026 EMVCo, LLC. All rights reserved. Reproduction, distribution and other use of this document is permitted only pursuant to the applicable agreement between the user and EMVCo found at www.emvco.com. EMV ® is a registered trademark or trademark of EMVCo, LLC in the United States and other countries. Reference Publication Name [ISO 8859] 8-bit character encodings. [ISO 639] Language codes EMV ® Contactless Specifications for Payment Systems Kernel 4 Specification v2.12 Page 4 / 151 © 2026 EMVCo, LLC. All rights reserved. Reproduction, distribution and other use of this document is permitted only pursuant to the applicable agreement between the user and EMVCo found at www.emvco.com. EMV ® is a registered trademark or trademark of EMVCo, LLC in the United States and other countries. 1.5 Notational Conventions 1.5.1 Use of Terms Terms and definitions are described in Book A: Architecture and General Requirements, with the addition of the following. Delayed Authorisation In cases where a reader has been deployed in an environment where a real time online transaction authorisation is never possible, a delayed authorisation may be performed. A “Delayed Authorisation” as referred to in this specification is processed by the reader as a Partial Online contactless transaction, with mandatory Offline Data Authentication. Separately from the initial reader and card interaction, a later authorisation request may be made to an Issuer’s system for the purposes of account verification or reservation of funds against an account. Partial Online A Partial Online contactless transaction is one where the card may be removed from the operating field of the reader after the first GENERATE AC response has been received. The result of the transaction is based on the response from the Issuer’s authorisation system. mPOS The term “mPOS” is used to refer to a mobile point of sale where a commercial off-the-shelf (COTS) device, such as a mobile phone or tablet, is used either standalone, to form contactless only mPOS system using the devices NFC interface, or in conjunction with a hardware accessory to form a contact and contactless mPOS system. The functions performed within the “Terminal” or “Reader” definitions may be provided by a mPOS device. 1.5.2 Reserved for Future Use (RFU) A bit specified as Reserved for Future Use (RFU) shall be set as specified, or to 0b if no indication is given. An entity receiving a bit specified as RFU shall ignore such a bit and shall not change its behaviour, unless explicitly stated otherwise. A data field having a value coded on multiple bits or bytes shall not be set to a value specified as RFU. An entity receiving a data field having a value specified as RFU, shall behave as defined by a requirement that specifically addresses the situation, or shall consider it a protocol error if no specific behaviour is defined. EMV ® Contactless Specifications for Payment Systems Kernel 4 Specification v2.12 Page 5 / 151 © 2026 EMVCo, LLC. All rights reserved. Reproduction, distribution and other use of this document is permitted only pursuant to the applicable agreement between the user and EMVCo found at www.emvco.com. EMV ® is a registered trademark or trademark of EMVCo, LLC in the United States and other countries. 1.6 mPOS Architectures This section describes the mPOS architectures that differ from the traditional POS systems that use specific devices designed for the purpose of acting as part or all of a card payment acceptance system. mPOS systems use commercial off-the-shelf (COTS) devices, such as mobile phones and tablets, as part or all of the card payment acceptance system. The following terms are used in the mPOS architecture: • mPOS (mobile Point Of Sale) – where a consumer mobile device forms part of a portable card acceptance system. • COTS (Commercial Off-The-Shelf) – a commercial off-the-shelf consumer mobile device such as a phone or tablet. • CPoC (Contactless Payment on COTS) – contactless payment using the NFC interface of a consumer mobile device. Where contactless transactions are performed directly with the NFC contactless interface of a COTS device, this is known as Contactless Payment on COTS (CPoC), also known as Tap on Phone. • SPoC (Software PIN on COTS) – PIN entry via a consumer mobile device. Where PIN entry is performed directly on to a COTS device, this is known as Software PIN on COTS (SPoC), also known as PIN on Glass. • Accessories – an additional hardware device or dongle that may provide card interfaces, PIN entry, amount entry, or display, that is to be used in conjunction with a COTS device to form an mPOS card acceptance system. An mPOS system will either: • comprise entirely of a COTS device only, or • may include additional devices to provide features such as card interfaces or PIN entry. The possible POS architectures are based on PIN entry and card interface locations and capabilities, as shown in Table 1-1: Terminal and mPOS Architectures Table 1-1: Terminal and mPOS Architectures Architecture Reference Terminal Architecture PIN Entry Location Contact Interface Location Contactless Interface Location Not applicable Traditional POS POS POS POS EMV ® Contactless Specifications for Payment Systems Kernel 4 Specification v2.12 Page 6 / 151 © 2026 EMVCo, LLC. All rights reserved. Reproduction, distribution and other use of this document is permitted only pursuant to the applicable agreement between the user and EMVCo found at www.emvco.com. EMV ® is a registered trademark or trademark of EMVCo, LLC in the United States and other countries. Architecture Reference Terminal Architecture PIN Entry Location Contact Interface Location Contactless Interface Location A (Accessory) COTS device and accessory 1 Accessory Accessory Accessory ASP (Accessory, Software PIN ) COTS device and accessory 1 supporting SPoC COTS device Accessory Accessory C Contactless COTS device supporting CPoC N/A N/A COTS device CSP Contactless, Software PIN COTS device supporting CPoC and SPoC COTS device N/A COTS device Notes: 1 If an accessory device is being used, it will provide a contact and contactless interface. The mandated and optional requirements, throughout this specification, are described in generic terms based on traditional POS systems. However, unless otherwise stated, any requirement in this specification is applicable to both traditional POS systems and mPOS systems. Where additional direction is needed for mPOS systems, clauses to include or exclude mPOS architectures are added using phrases such as applicable/not applicable, supported/not supported or including/excluding. References to requirements and functions specific to mPOS architectures are indicated by the prefix “mPOS-“. The mPOS Requirements for the various architectures are detailed in Annex C. Note: Security and functional approvals are determined based on whether mPOS functionality is provided by a dedicated accessory device or by software on the COTS device directly. EMV ® Contactless Specifications for Payment Systems Kernel 4 Specification v2.12 Page 7 / 151 © 2026 EMVCo, LLC. All rights reserved. Reproduction, distribution and other use of this document is permitted only pursuant to the applicable agreement between the user and EMVCo found at www.emvco.com. EMV ® is a registered trademark or trademark of EMVCo, LLC in the United States and other countries. 1.7 Overview This volume includes the following sections and annexes: Section 1 contains general information that helps the reader understand and use this specification. Section 2 describes the Contactless EMV Mode in which a contactless card and reader can operate and details the different flows that a contactless transaction can take. Section 3 provides a high-level overview of processing according to this specification. Section 4 – 13 detail the different steps that occur in a contactless transaction and specify the command and processing requirements for each step of the transaction. Annex A details the data elements used in contactless transaction processing using Kernel 4. Annex B details the Configuration Data that is provided to the kernel by the Terminal and by Entry Point. Annex C details the mPOS requirements Annex D - Glossary is a glossary of terms and abbreviations used in this specification. EMV ® Contactless Specifications for Payment Systems Kernel 4 Specification v2.12 Page 9 / 151 © 2026 EMVCo, LLC. All rights reserved. Reproduction, distribution and other use of this document is permitted only pursuant to the applicable agreement between the user and EMVCo found at www.emvco.com. EMV ® is a registered trademark or trademark of EMVCo, LLC in the United States and other countries. 2 Contactless EMV Mode and Transaction Flows This section describes the mode in which a contactless card and reader can operate. It also details the different flows that a contactless transaction can take. 2.1 Contactless EMV Mode of Operation This specification supports only EMV Mode in which the Card and Terminal can operate. This specification no longer supports Magstripe Mode: • EMV mode – This mode of operation is designed for Issuers and Acquirers supporting EMV data in the authorisation and clearing messages. 2.1.1 Transaction support for Contactless EMV Mode All Readers (including all mPOS architectures) must implement and support only EMV mode, and must not implement and support Magstripe Mode (as per requirements in section 4.3.7). Whether a transaction is capable of proceeding in EMV mode is determined by the ability of the Card and the Terminal to both support EMV mode, as shown in Table 2-1. Table 2-1: Contactless Mode Selection Reader Configured to Support EMV Mode Only Card Supports Mag-Stripe Mode only Not supported. Cardholder is instructed to try another interface, if supported, or try another means of payment. For mPOS-C, mPOS-CSP - Not supported. Cardholder is instructed to try another means of payment. Card Supports Both Mag-Stripe and EMV Modes EMV mode transaction Card Supports EMV mode only EMV Mode transaction EMV ® Contactless Specifications for Payment Systems Kernel 4 Specification v2.12 Page 10 / 151 © 2026 EMVCo, LLC. All rights reserved. Reproduction, distribution and other use of this document is permitted only pursuant to the applicable agreement between the user and EMVCo found at www.emvco.com. EMV ® is a registered trademark or trademark of EMVCo, LLC in the United States and other countries. In this version of the specification Bit 7 and Bit 8 in Contactless Reader Capabilities (Tag '9F6D') will always be set, resulting in Terminal Type – Modified (shown in Table 4-3) Bit 7 and Bit 8 also set. Similarly, Byte 1 Bit 4 to Bit 7 in the Enhanced Contactless Reader Capabilities (shown in Table 4-4) are set to ‘1100'. This data is usually provided to the Card during the GET PROCESSING OPTIONS command. The configuration of Terminal Type – Modified and Enhanced Contactless Reader Capabilities should not be set with conflicting values. If the card requests Terminal Type via the Processing Options Data Object List (PDOL) in the GET PROCESSING OPTIONS command, the reader instead returns Terminal Type – Modified (as described in section 4.3). If the card requests the Enhanced Contactless Reader Capabilities via the Processing Options Data Object List (PDOL) in the GET PROCESSING OPTIONS command the reader shall return the Enhanced Contactless Reader Capabilities. The resulting Terminal Type – Modified and/or the Enhanced Contactless Reader Capabilities data element is requested by the Card via the PDOL to enable the Card to determine its transaction mode. The Card indicates which mode it supports for the transaction in the Application Interchange Profile (AIP) Byte 2 Bit 8 – it is set to 1b to indicate that the Card and Issuer support both EMV and Magstripe Mode, and to 0b to indicate that only Magstripe Mode is supported. The reader shall follow requirements 4.3.7.1 to 4.3.7.3 in order to determine transaction support for EMV Mode. 2.1.2 [Section removed] The content in this section has been purposely removed from this specification, as Expresspay Magstripe Mode is no longer supported. 2.1.3 [Section removed] The content in this section has been purposely removed from this specification, as Expresspay Magstripe Mode is no longer supported. 2.1.4 Contactless EMV Mode Transactions When a contactless transaction is performed in EMV mode, the reader is capable of sending the standard EMV data elements and there are no restrictions. 2.1.5 Contactless Mobile Transaction When a transaction is performed as Contactless Mobile the reader may prompt for an action to be performed on the Mobile device by exiting the transaction with a Try Again Outcome. EMV ® Contactless Specifications for Payment Systems Kernel 4 Specification v2.12 Page 11 / 151 © 2026 EMVCo, LLC. All rights reserved. Reproduction, distribution and other use of this document is permitted only pursuant to the applicable agreement between the user and EMVCo found at www.emvco.com. EMV ® is a registered trademark or trademark of EMVCo, LLC in the United States and other countries. A Contactless Mobile: • Follows the Contactless EMV Mode of Operation requirements as per section 4.3.7. • May support Mobile CVM as per section 2.1.5.1. 2.1.5.1 Mobile CVM Contactless Mobile supports the Mobile CVM. This permits cardholder authentication on the Card using one of the mobile based authentication methods available. The reader manages the requirements for Cardholder Verification and processes the CVM List as for EMV. However, the reader performs no part in the Mobile CVM verification process – the Mobile CVM is captured and verified by an application on the Card, prior to the transaction. The results are passed to the reader as Mobile CVM Results in the response to the GET PROCESSING OPTIONS command or as an exception code in the response to the GENERATE AC command. 2.2 Contactless Transaction Processing A contactless transaction can be performed in the following ways: • Offline (not supported for mPOS-C, mPOS-CSP terminals) • Partial Online with either: • Immediate authorisation or • Delayed authorisation (a “Delayed Authorisation” transaction). This shall not be supported for mPOS-C, mPOS-CSP terminals. Figure 2-1 shows the transaction flow for a contactless transaction and highlights the different processes performed for each of these options. EMV ® Contactless Specifications for Payment Systems Kernel 4 Specification v2.12 Page 12 / 151 © 2026 EMVCo, LLC. All rights reserved. Reproduction, distribution and other use of this document is permitted only pursuant to the applicable agreement between the user and EMVCo found at www.emvco.com. EMV ® is a registered trademark or trademark of EMVCo, LLC in the United States and other countries. Figure 2-1: Transaction Flow Overview Unable to go online? Card Activation Application Selection Init application processing Read application data Offline data authentication Processing restrictions Cardholder verification Terminal risk management 1 st terminal action analysis 1 st card action analysis Online transaction? Transaction completion Offline Partial online Offline data authentication CDA sig check Entry Point Processing Delayed authorisation Try again End Application Try another interface Approved Declined Authorisation type? Conditional Step Mandatory Step Legend Online processing Yes No Yes Delayed Immediate No 2.2.1 Premature card removal If the cardholder removes the card from the operating field without being prompted to do so, then the kernel returns control to Entry Point, passing an Outcome of Try Again with the following parameter settings: EMV ® Contactless Specifications for Payment Systems Kernel 4 Specification v2.12 Page 13 / 151 © 2026 EMVCo, LLC. All rights reserved. Reproduction, distribution and other use of this document is permitted only pursuant to the applicable agreement between the user and EMVCo found at www.emvco.com. EMV ® is a registered trademark or trademark of EMVCo, LLC in the United States and other countries. Start B Online Response Data N/A CVM N/A UI Request on Outcome Present Yes • Message Identifier: '21' (“Present Card Again”) • Status: Processing Error • Hold Time: 0 • Language Preference UI Request on Restart Present Yes • Message Identifier: '21' (“Present Card Again”) • Status: Ready to Read. • Hold Time: 0 • Language Preference Data Record Present No Discretionary Data Present No Alternate Interface Preference N/A Receipt N/A Field Off Request N/A Removal Timeout Zero Requirements – Card Early Removal 2.2.1.1 If the card leaves the operating field before the cardholder is prompted to remove it from the field, then the reader shall invoke the User Interface Request Message to display Message Identifier: '21' (“Present Card Again”) and return control to Entry Point. EMV ® Contactless Specifications for Payment Systems Kernel 4 Specification v2.12 Page 14 / 151 © 2026 EMVCo, LLC. All rights reserved. Reproduction, distribution and other use of this document is permitted only pursuant to the applicable agreement between the user and EMVCo found at www.emvco.com. EMV ® is a registered trademark or trademark of EMVCo, LLC in the United States and other countries. 2.2.2 Offline Transaction During an offline transaction, the card and reader either approve or decline a transaction without further online processing. The enablement of Offline Data Authentication is mandatory for the deployment of terminals in offline environments. Only 1st Terminal Action Analysis and 1st Card Action Analysis are performed. mPOS-C, mPOS-CSP terminals do not support offline transactions and shall be online only readers. Requirements – Offline Transaction 2.2.2.1 If a reader indicates that it is offline capable (by setting bits 3-1 of Terminal Type (Tag '9F35') appropriately), then the reader shall be able to perform an offline transaction. 2.2.3 Partial Online Transaction In a Partial Online transaction, the interaction between the card and the reader ends after 1 st Card Action Analysis has completed. The enablement of Offline Data Authentication is mandatory for the deployment of terminals in online capable environments where offline transactions are also possible. The result of the transaction is based on the response from the Issuer’s authorisation system. Requirements – Partial Online Transaction 2.2.3.1 If a reader indicates that it is online capable (by setting bits 3-1 of Terminal Type (Tag '9F35') appropriately), then the reader shall be able to perform a Partial Online transaction (i.e. without a second GENERATE AC being sent to the card). A reader performing a Partial Online transaction shall prompt the cardholder to remove the card from the field immediately after the completion of 1 st Card Action Analysis. The card should be removed from the operating field only when the reader indicates that it is time to do so. Once the reader has indicated that the card can be removed, whether the card is actually removed or not, the reader will continue to process the transaction as planned. Requirements – Partial Online Transaction Completion 2.2.3.2 If a reader is online capable, and the reader is conducting a Partial Online transaction, then the reader shall complete the transaction as a Partial Online transaction whether the user leaves the card in the field or removes the card when instructed to do so. EMV ® Contactless Specifications for Payment Systems Kernel 4 Specification v2.12 Page 15 / 151 © 2026 EMVCo, LLC. All rights reserved. Reproduction, distribution and other use of this document is permitted only pursuant to the applicable agreement between the user and EMVCo found at www.emvco.com. EMV ® is a registered trademark or trademark of EMVCo, LLC in the United States and other countries. 2.2.4 Delayed Authorisation In cases where a reader has been deployed in an environment where a real time online transaction authorisation is not possible, a delayed authorisation may be performed. A reader indicates it supports Delayed Authorisations by setting the Enhanced Contactless Reader Capabilities Byte 4 Bit 7 to 1b. A “Delayed Authorisation” as referred to in this specification is processed by the reader as a partial online transaction, with the interaction between the Card and reader being completed after the 1st Card Action Analysis. Offline Data Authentication support is mandatory for all readers supporting Delayed Authorisations. The enablement of Offline Data Authentication is mandatory for the deployment of terminals in delayed authorization environments. If it is determined that the transaction is to be sent online, the transaction shall be approved at the Terminal and a subsequent delayed authorisation request is made to an Issuer’s authorisation system for the purposes of account verification or reservation of funds against an account. mPOS-C and mPOS-CSP terminals shall not support delayed authorization. Requirements – Delayed Authorisation 2.2.4.1 If the Enhanced Contactless Reader Capabilities Byte 4 Bit 7 to 1b, and Offline Data Authentication has been performed successfully, then the reader shall be able to approve the transaction and perform a Partial Online with delayed authorisation transaction. 2.2.4.2 If the Enhanced Contactless Reader Capabilities Byte 4 Bit 7 to 1b, and the Card returns an AAC in response to the first GENERATE AC, then the reader shall not perform Offline Data Authentication and the transaction shall be declined. EMV ® Contactless Specifications for Payment Systems Kernel 4 Specification v2.12 Page 16 / 151 © 2026 EMVCo, LLC. All rights reserved. Reproduction, distribution and other use of this document is permitted only pursuant to the applicable agreement between the user and EMVCo found at www.emvco.com. EMV ® is a registered trademark or trademark of EMVCo, LLC in the United States and other countries. 2.3 Contactless Transaction Configurations The options for all possible combinations of processing a contactless transaction are shown in Table 2-2. Table 2-2: Contactless Transaction Combinations Contactless Terminal Configuration Card Supports either EMV Mode only or Card Supports Both Mag-Stripe and EMV Modes EMV Mode supported Partial Online with delayed authorisation (Not applicable for mPOS-C, mPOS-CSP) The EMV transaction flow is performed until 1 st Card Action Analysis is completed. Offline Data Authentication is mandatory. A card that supports EMV Mode will present a CDOL for Cryptogram Version '01', ‘32’ or ‘33’. An online authorisation is performed at a later time. EMV Mode supported Offline (Not applicable for mPOS-C, mPOS-CSP) An offline transaction is performed, if offline is allowed by Issuer configuration settings and Card Risk Management. Offline Data Authentication is mandatory. A card that supports EMV Mode will present a CDOL for Cryptogram Version ‘01’, ‘32’ or ‘33’. EMV Mode supported Partial Online with immediate authorization The EMV transaction flow is performed until 1st Card Action Analysis is completed. A Card that supports Expresspay EMV Mode will present a CDOL for Cryptogram Version ‘01’, ‘32’ or ‘33’. After going online, the transaction result will be based on the Issuer authorization response. In case of mPOS-C or CSP, if an online connection is not possible prior to the transaction, then the transaction shall not be started. This specification supports the terminal configurations listed in Table 2-3. EMV ® Contactless Specifications for Payment Systems Kernel 4 Specification v2.12 Page 17 / 151 © 2026 EMVCo, LLC. All rights reserved. Reproduction, distribution and other use of this document is permitted only pursuant to the applicable agreement between the user and EMVCo found at www.emvco.com. EMV ® is a registered trademark or trademark of EMVCo, LLC in the United States and other countries. Table 2-3: Reader Configurations Reader Configuration Definition Offline only (Not applicable for mPOS-C, mPOS-CSP) Offline only readers do not have the ability to obtain a real time online authorisation nor do they have the ability to connect online for an authorisation at a later date. Offline Only readers must perform Offline Data Authentication on all transactions. Online only Online only readers require all transactions to be sent online for authorisation and do not have the ability to approve transactions offline. Readers configured in this way do not need to enable Offline Data Authentication. The reader must decline the transaction if it is unable to go online to obtain an authorisation. Offline with Online Capability (Not applicable for mPOS-C, mPOS-CSP) Readers configured in this way are able to process transactions offline or send the transaction online for authorisation if required. Readers configured in this way must enable Offline Data Authentication. Readers of this type shall be capable of being configured to operate as Online Only readers. EMV ® Contactless Specifications for Payment Systems Kernel 4 Specification v2.12 Page 18 / 151 © 2026 EMVCo, LLC. All rights reserved. Reproduction, distribution and other use of this document is permitted only pursuant to the applicable agreement between the user and EMVCo found at www.emvco.com. EMV ® is a registered trademark or trademark of EMVCo, LLC in the United States and other countries. Reader Configuration Definition Delayed Authorisations (Not applicable for mPOS-C, mPOS-CSP) In cases where a reader has been deployed in an environment where real time online transaction authorisation is never possible, a delayed authorisation may be performed. Readers configured in this way must enable Offline Data Authentication. A “Delayed Authorisation” as referred to in this specification is processed by the reader as a Partial Online contactless transaction, with mandatory Offline Data Authentication (unless the card has returned an AAC in response to the first GENERATE AC command, in which case ODA does not need to be performed). Separately from the initial reader and card interaction, a later authorisation request may be made to an Issuer’s system for the purposes of account verification or reservation of funds against an account. EMV ® Contactless Specifications for Payment Systems Kernel 4 Specification v2.12 Page 19 / 151 © 2026 EMVCo, LLC. All rights reserved. Reproduction, distribution and other use of this document is permitted only pursuant to the applicable agreement between the user and EMVCo found at www.emvco.com. EMV ® is a registered trademark or trademark of EMVCo, LLC in the United States and other countries. Requirements – Transaction Combinations 2.3.1.1 If the terminal is performing a Partial Online transaction in EMV mode with an EMV card, then the card may be removed after the 1 st Card Action Analysis and the terminal shall complete the Partial Online transaction in EMV mode. 2.3.1.2 If an offline terminal is EMV capable, and the terminal is performing a transaction satisfying risk management requirements with an EMV card, then the card may be removed after the 1 st Card Action Analysis and Offline Data Authentication is performed, and the terminal shall complete the transaction in EMV mode. EMV ® Contactless Specifications for Payment Systems Kernel 4 Specification v2.12 Page 20 / 151 © 2026 EMVCo, LLC. All rights reserved. Reproduction, distribution and other use of this document is permitted only pursuant to the applicable agreement between the user and EMVCo found at www.emvco.com. EMV ® is a registered trademark or trademark of EMVCo, LLC in the United States and other countries. 3 Processing Overview The following sections provide detailed information about the interaction between the contactless card and reader during a transaction. All functions mentioned in the following sections are performed as described in this specification where detailed or otherwise as described within [EMV 4.4 Book 1] – [EMV 4.4 Book 3]. Some functionality supported by EMV is not permitted or is restricted for contactless transactions. Card Activation and Application Selection shall be performed as in Book B: Entry Point Specification, with new transactions being initiated at Start A or Start B as described in Book B. Figure 2-1 shows an overview of the contactless transaction flow from the point at which a contactless card is introduced into the operating field of a reader to the point when the reader completes the transaction. After processing a contactless transaction, the kernel returns control to Entry Point by passing an Outcome that specifies required actions from Entry Point or the terminal (POS System). Control may subsequently return to the kernel via Book B Start B. This ‘restart’ mechanism enables the kernel to process a retry for failed Mobile CVM processing. The FCI data made available to the kernel by Entry Point may contain Language Preference Code (Tag '5F2D'), which may be supplied as one of the Outcome parameters in order to indicate a preferred language for the display of User Interface Messages. According to Book A, Figure 5-2: Logical Architecture, the Terminal is responsible for any Additional processing (including Online Authorisation) and other services during a transaction. Hence, it may need to retrieve Kernel/Reader data (static and dynamic) and/or Card public data (read from the Card but not stored in the Kernel after the transaction is finished). As per the description of the Outcome Parameters in Book A, section 6.2, the Data Record and Discretionary Data parameters are the mechanisms the Kernel has to provide data to the Entry Point, Reader and consequently, the Terminal. Data Record minimum data elements are defined in Annex A.4 for Online Authorisation and Clearing. For the Terminal to retrieve any data it needs from the Kernel, for additional processing and services, it must use the Discretionary Data Object List Configuration Data (see Annex B.1 for details). The data elements present in this data object list will, if available, be included in the Discretionary Data Outcome Parameter and the Discretionary Data Present parameter will be set to Yes for the following Outcomes: Approved, Declined, Online Request and Request Online PIN. EMV ® Contactless Specifications for Payment Systems Kernel 4 Specification v2.12 Page 21 / 151 © 2026 EMVCo, LLC. All rights reserved. Reproduction, distribution and other use of this document is permitted only pursuant to the applicable agreement between the user and EMVCo found at www.emvco.com. EMV ® is a registered trademark or trademark of EMVCo, LLC in the United States and other countries. 4 Initiate Application Processing 4.1 Overview During Application Initiation, the reader signals to the card that processing of the transaction is beginning. Initiate Application Processing is performed as described in [EMV 4.4 Book 3] and [EMV 4.4 Book 4]. Upon receipt of the Application File Locator (AFL) and Application Interchange Profile (AIP), the reader proceeds to read the application data records from the card. The AFL is a list of parameters identifying the files and records to be read from the card used in processing the transaction. The AIP indicates the capabilities of the card to support specific functions of the application to be taken into consideration by the reader when determining how to process the transaction. 4.2 Commands • GET PROCESSING OPTIONS To support Initiate Application Processing as described in [EMV 4.4 Book 3], section 10.1, the card must support the GET PROCESSING OPTIONS command as described in the following section. If the transaction is taking place as Contactless Mobile, then Mobile CVM Results shall be returned in the GET PROCESSING OPTIONS response. (See on Table 8-1: Mobile CVM Results – Tag '9F71') Requirements – GET PROCESSING OPTIONS 4.2.1.1 A reader shall send the GET PROCESSING OPTIONS command to the card following Application Selection. EMV ® Contactless Specifications for Payment Systems Kernel 4 Specification v2.12 Page 22 / 151 © 2026 EMVCo, LLC. All rights reserved. Reproduction, distribution and other use of this document is permitted only pursuant to the applicable agreement between the user and EMVCo found at www.emvco.com. EMV ® is a registered trademark or trademark of EMVCo, LLC in the United States and other countries. 4.3 Processing Requirements 4.3.1 Pre-PDOL Processing The reader must reset Contactless Reader Capabilities Byte 1 Bit 4 to 0b, ‘CVM Not Required’ and Enhanced Contactless Reader Capabilities Byte 3 to ‘00', since these are specific only to the context of the current transaction. All other Enhanced Contactless Reader Capabilities settings (bytes 1, 2 and 4) are defined at Terminal configuration. If the reader CVM Required Limit Exceeded indicator is set, then the reader shall set: • Contactless Reader Capabilities Byte 1 Bit 4 to 1b, ‘CVM Required’ • Enhanced Contactless Reader Capabilities Byte 3 Bit 7 to 1b, ‘CVM Required’ If the reader is an offline-only (i.e. if the Terminal Type is 'x3' or 'x6') or the reader can determine that it is currently unable to go online for authorisation, (excluding mPOS-C, mPOS-CSP), then it will set Enhanced Contactless Reader Capabilities Byte 3 Bit 8 to 1b, ‘Reader is Unable to go online’. For mPOS-C or mPOS-CSP terminal types, if the terminal can determine that it is currently Unable to go Online for authorization, then the kernel returns control to Entry Point, passing a Final Outcome of End Transaction. EMV ® Contactless Specifications for Payment Systems Kernel 4 Specification v2.12 Page 23 / 151 © 2026 EMVCo, LLC. All rights reserved. Reproduction, distribution and other use of this document is permitted only pursuant to the applicable agreement between the user and EMVCo found at www.emvco.com. EMV ® is a registered trademark or trademark of EMVCo, LLC in the United States and other countries. Requirements – Pre-PDOL Processing 4.3.1.1 The reader shall reset Contactless Reader Capabilities Byte 1 Bit 4 to 0b, ‘CVM Not Required’ and Enhanced Contactless Reader Capabilities Byte 3 to 00. 4.3.1.2 If the Reader CVM Required Limit Exceeded indicator is set then the reader shall set Contactless Reader Capabilities Byte 1 Bit 4 to 1b, ‘CVM Required’, and shall set Enhanced Contactless Reader Capabilities Byte 3 Bit 7 to 1b, ‘CVM Required’. 4.3.1.3 If the reader is an offline-only reader (Reader type 'x3' or 'x6') or the reader has determined that it is unable to go online, then the reader shall set Enhanced Contactless Reader Capabilities Byte 3 Bit 8 to 1b, ‘Reader is Unable to go online’. 4.3.1.4 If the reader is a mPOS-C or mPOS-CSP, and Unable to go Online then the terminal shall decline the transaction, returning control to Entry Point as defined in 13.3. 4.3.2 PDOL Processing The reader determines whether the optional PDOL was supplied by the card application in response to Application Selection. If the PDOL is not present, then the reader formats the GET PROCESSING OPTIONS command with the command data field of '8300'. Requirements – GPO Without PDOL Data 4.3.2.1 If the card did not specify a PDOL in the response to Application Selection, then the reader shall send the GET PROCESSING OPTIONS command with the command data field set to '8300'. If the PDOL was received, the reader formats the GET PROCESSING OPTIONS command to include the data elements requested in the PDOL to be sent to the card with this command. The data elements for the PDOL must be formatted as defined by [EMV 4.4 Book 3], section 5.4. Requirements – PDOL Data in GPO 4.3.2.2 If the card specified a PDOL in response to Application Selection, then the reader shall send the GET PROCESSING OPTIONS command with the requested PDOL data, except as described in requirement 4.3.3.1. EMV ® Contactless Specifications for Payment Systems Kernel 4 Specification v2.12 Page 24 / 151 © 2026 EMVCo, LLC. All rights reserved. Reproduction, distribution and other use of this document is permitted only pursuant to the applicable agreement between the user and EMVCo found at www.emvco.com. EMV ® is a registered trademark or trademark of EMVCo, LLC in the United States and other countries. 4.3.3 Terminal Type – Modified If the PDOL requested Terminal Type (Tag '9F35') and does not contain the Enhanced Contactless Reader Capabilities (Tag ‘9F6E’), the reader returns Terminal Type – Modified (as shown in Table 4-3) instead of Terminal Type. These values are set by the reader based on the Terminal Type combined (OR’d) with a proprietary data element, Contactless Reader Capabilities (Tag '9F6D'), that is stored in the reader. See Table 4-1 and Table 4-2 for the values of these data elements. Note that the Terminal Type – Modified value is transient and valid for the purpose of determining whether contactless EMV mode is supported by both the Terminal and the Card for the current transaction being processed. The value of the (unmodified) Termina