What is Form 27, and who has to file it?

Section 146(2) of the Patents Act requires the patentee, and every licensee, to tell the Patent Office whether the patented invention is being worked commercially in India. The statement is filed on Form 27 under Rule 131.

The obligation is independent for each party. A licensee's duty is not discharged by the patentee filing, and vice versa. Where several related patents are held by the same patentee, a single Form 27 may cover them.

There is no direct counterpart to this requirement in most other jurisdictions, which is why it is frequently missed by foreign patentees managing Indian portfolios from abroad.