It follows reports last August which led to his resignation as a Minister of State.
The Standards in Public Office Commission has released its investigation report into allegations involving Fianna Fáil's Robert Troy.
The report's findings state the Deputy Troy contravened section five of the Ethics Act for not declaring "registrable interest" in the years 2020 and 2021.
Reports came to light in August 2022 the Longford-Westmeath TD did not properly declare his full business interests, as per Dáil rules.
It led to his resignation as a Minister of State, after he claimed to have made genuine errors with his statutory declaration.
SIPO has today found Deputy Troy failed to declare five rental properties in Westmeath and one in Phibsborough, Dublin; he failed to declare a contract with Westmeath County Council under the Rental Accommodation Scheme; and he did not declare he was a director of RMT Management Limited.
The report also found he acted in good faith and wouldn't have made errors had he sought help with the documents.