18 CFR § 35.9 - Requirements for filing rate schedules, tariffs or service agreements.
(a) Rate schedules, tariffs, and service agreements may be filed either by dividing the rate schedule, tariff, or service agreements into individual sheets or sections, or as an entire document except as provided in paragraphs (b) and (c) of this section.
(b) Open Access Transmission Tariffs (OATT) filed by utilities that are not Independent System Operators or Regional Transmission Organizations must be filed either as individual sheets or sections. If filed as sections, the sections must be no larger than the 1.0 level, although each schedule or attachment may be a single section. Individual service agreements that are entered into pursuant to the OATT may be filed as entire documents.
(c) OATT and other open access documents filed by Independent System Operators or Regional Transmission Organizations must be filed either as individual sheets or sections. If filed as sections, the sections must be no larger than the 1.1 level, including schedules or attachments. Individual service agreements that are part entered into pursuant to the OATT may be filed as entire documents.