Patent of addition

Patent of addition can be filed under section 54 and it claims any modifications or improvements over the invention disclosed in the main patent

It can be filed anytime before the grant of the main patent.

Form-1 has to be filed with prescribed fee mentioning the details fo the main patent.

It will be published , examined in tghe usual way as that of the main patent and cannot be objected on the ground of lack of inventive step based on the main patent.

The priority / filing date will be same as that of the main patent.

Patent of addition will be granted only after the grant of the main patent.

It will expire along with the main patent and no renewal fee has to be paid.

Rightly described by Navya.

Navya: I do not seem to fully agree with your statement

"It [patent of addition] can be filed anytime before the grant of the main patent".

 In my assessment a patent of addition can also filed after the grant of main patent for any improvement that you make. There are no limitations under chapter IX Secs 54-56 that it needs to be filed before the grant of the main patent only.

Dear sir,

Thanks for correcting me.

patent of addition can be filed anytime starting from the date of filing of Parent application till the date of expiry of the parent application.

Aslo one more point is request for examintaion has to be filed within 48 months from the date of filing patent of addition.

Even though it has a priority datye of main patent. Got to know froma recent case history.

Anyone confirm the same.

The pirority date will be of the main patent.

Further RFE can be filed after publication (18 Months if not requested for earlt publication U/s 11A) and within 48 Months. Here we have to note that the time datum is the application date and not pirority date for patent of addition 

The date on which the improvement is disclosed to the patent office ie the date of filing the patent of addition is the date from which the protection starts and ends at the date on which the main patent expires.Normally if the improvement is of a minor nature it is better to file a patent of addition and avoid paying renewal fees.

T.R.Subramanian