The different figures must be numbered consecutively in Arabic numerals, independently of the numbering of the sheets.[Rule 46(2)(h); ]
This numbering should be preceded by the abbreviation "FIG", whatever the official language of the application. Where a single figure is sufficient to illustrate the invention, it should not be numbered and the abbreviation "FIG" must not appear. Rule 46(2)(d) also applies to numbers and letters identifying the figures, i.e. they must be simple and clear and may not be used in association with brackets, circles, or inverted commas. They should also be larger than the numbers used for reference signs.[Rule 46(2)(d); ]
An exception to Rule 46(2)(h) referred to above may be permitted only as regards partial figures intended to form one whole figure, irrespective of whether they appear on one or several sheets. In this case the whole figure may be identified by the same number followed by a capital letter (e.g. FIG 7A, FIG 7B).
Source: http://www.epo.org/law-practice/legal-texts/html/guidelines/e/a_ix_5_2.htm
Date retrieved: 17 May 2021