# Article 9 — Identification of person or computer algorithm responsible for execution of a transaction **Commission Delegated Regulation (EU) 2017/590 · binding · OJ L 87, 31.3.2017 · dated 28 Jul 2016 [in force]** *In force · Commission Delegated Regulation (EU) 2017/590, OJ L 87, 31.3.2017 · Checked against EUR-Lex on 26 Oct 2026 · [Official source](https://eur-lex.europa.eu/eli/reg_del/2017/590/oj/eng)* 1. Where a person or computer algorithm within the investment firm which executes a transaction determines which trading venue, systematic internaliser or organised trading platform located outside the Union to access, which firms to transmit orders to or any conditions related to the execution of an order, that person or computer algorithm shall be identified in field 59 of Table 2 of Annex I. 1. Where a person within the investment firm is responsible for the execution of the transaction, the investment firm shall assign a designation for identifying that person in a transaction report in accordance with Article 6. 1. Where a computer algorithm within the investment firm is responsible for the execution of the transaction, the investment firm shall assign a designation for identifying the computer algorithm in accordance with Article 8(3). 1. Where a person and computer algorithm are both involved in execution of the transaction, or more than one person or algorithm are involved, the investment firm shall determine which person or computer algorithm is primarily responsible for the execution of the transaction. The person or computer algorithm taking primary responsibility for the execution shall be determined in accordance with pre-determined criteria established by the investment firm.