Where ESMA finds serious indications of possible infringements of Title IVa it shall appoint an independent investigation officer who has not been directly or indirectly involved in the supervision or authorisation of the data reporting services provider concerned. The officer shall investigate alleged infringements, take into account comments from the persons investigated, request information under Article 38b, conduct investigations and on‑site inspections under Articles 38c and 38d, and have access to all documents and information gathered by ESMA in its supervisory activities.

Before submitting a complete file the officer shall give the persons an opportunity to be heard, base findings only on facts on which those persons had the opportunity to comment and ensure the rights of the defence. Upon submission ESMA shall notify the persons who may access the file subject to protection of business secrets and third‑party confidential information. ESMA will decide on infringements and may take supervisory measures under Article 38g; the officer shall not participate in ESMA's decision‑making. The Commission shall adopt delegated acts by 1 October 2021 to specify procedures for fines and periodic penalty payments. ESMA shall refer matters for criminal prosecution where serious indications of a criminal offence and shall refrain from imposing fines or periodic payments where a prior acquittal or conviction on identical or substantially the same facts has acquired the force of res judicata under national law.