1. Failure to file within the prescribed time limit a declaration or deed containing an indication of items to be taken into account for the assessment or liquidation of the tax shall result in the application, to the amount of duties charged to the taxpayer or resulting from the declaration or deed filed late, of an increase of:
a. 10% in the absence of a formal notice or in the event that the declaration or deed is filed within thirty days of receipt of a formal notice, served by registered post, to produce it within this period;
b. 40% where the declaration or deed has not been filed within thirty days of receipt of a formal notice, served by registered post, to produce it within that period;
c. 80% in the event of the discovery of a concealed activity or, as regards the development tax provided for in Article 1635 quater A, in the event of construction or development without authorisation.
2. For the declarations provided for in article 800, the 10% increase is applicable from the first day of the seventh month following that of the expiry of the six-month and twenty-four-month periods provided for respectively in articles 641 and 641 bis.
The 40% increase applies when this declaration has not been filed within ninety days of receipt of a formal notice, served by registered letter to have, to file it within this period.
3. In the event of delay in carrying out the merged formality provided for in article 647, no account shall be taken of the period between the filing of the refused document and the new presentation for formality if the latter occurs within one month of notification of the refusal.
4. When the declaration of all income provided for in article 170 filed after the deadline includes items from one or more category income tax returns also filed after the deadline and several increases at different rates are incurred, these increases are applied to the income tax apportioned in proportion to the income representing each offence. However, the rate of the increase incurred in respect of the overall income tax return applies to the entire tax when it is higher than that applicable in respect of the other returns.
5. For the reporting obligations provided for in Article 982 , the 10% increase provided for in a of 1 of this Article is increased to 40% when the filing follows the disclosure of foreign assets that were not subject to the reporting obligations provided for in articles 1649 A, 1649 AA and 1649 AB.