the grounds under which a patent may be revoked under s. 64 (1). There are in all 17grounds listed in the section. Broadly they may be grouped under three heads as follows:

Grounds relating to the rights of the patentee and his conduct.

1.Patentee not entitled to the patent-----s. 64 (1) (b)

.2.Patent wrongfully obtained as against the person entitled---s. 64 (1) (c).

3.Patent obtained by false suggestion or representation----s. 64 (1) (j).

4.Failure to disclose information regarding foreign applications — s. 64 (1) (m)

5.Noncompliance with directions for secrecy---s. 64 (1) (n).

6.Amendment of specification obtained by fraud---s. 64 (1) (o).

Grounds relating to the invention and its quality.

1.Subject of a claim not an invention---s. 64 (1) (d)

 2.Subject of a claim not a patentable invention---s. 64 (1) (k)

 3.Invention claim was secretly used before the priority date--- s. 64 (1) (l)

 4.Invention has claimed already the subject of a prior grant----s. 64 (1) (a)

 5.Invention lacks novelty having regard to prior knowledge or prior use---s. 64 (1) (e).

 6.Invention is obvious or does not involve an inventive step having regard to prior knowledge orprior use---s. 64 (1) (f).

 7.Invention not useful-----s. 64 (1) (g).

 8.The invention claimed was anticipation having regard to the knowledge, oral or otherwisewithin any local or indigenous community in India or elsewhere, ---s. 64 (1) (q).

Grounds relating to a description of the invention.

1.Invention not sufficiently described----s. 64 (1) (h).

 2.Claims not clearly defined and not fairly based — s. 64 (1) (I).

 3.The complete specification does not disclose or wrongly mention the source or geographical originof biological material