Article 74 Hours of business
The Patent Office shall be deemed to be closed at the following hours for the transaction of business of the classes specified—
(a)
on weekdays, other than Saturdays, at midnight for the filing of applications, forms and other documents, and at four p.m. for all other business,
(b)
on Saturdays, at one p.m. for the filing of new applications for the registration of designs which are not convention applications.