OCI has all the rights except to vote or hold any contitutional govt posts. please refer to the comparative char issued by MHA.
Open web site mha.nic.in/pdfs/oci-chart.pdf
Comparative Chart on NRI/PIO/PIO CARD HOLDERS/OCI
NRI PIO PIO Card Holder OCI
1.Who ? An Indian
citizen who
is ordinarily
residing
outside
India and
holds an
Indian
Passport
A person
who or whose
any of
ancestors was
an Indian
national and
who is
presently
holding
another
country’s
citizenship/
nationality i.e.
he/she is
holding
foreign
passport
A person registered as
PIO Card Holder under
MHA’s scheme vide
Notification No.
26011/4/98-F.I dated
19.08.2002.
A person registered as
Overseas Citizen of India
(OCI) under section 7A
of the Citizenship Act,
1955
2. Who is
eligible?
- - Any person who at any
time held an Indian
Passport; or he or either
of his parents or grand
parents was born in or
was permanently resident
in India as defined in
Government of India Act,
1935 and other territories
that became part of India
thereafter provided
neither was at any time a
citizen of Afghanistan,
Bhutan, China, Nepal,
Pakistan and Sri Lanka;
or who is a spouse of a
citizen of India or a
person of Indian origin as
mentioned above.
A foreign national, who
was eligible to become
citizen of India on
26.01.1950 or was a
citizen of India on or at
anytime after 26.01.1950
or belonged to a territory
that became part of India
after 15.08.1947 and
his/her children and
grand children, provided
his/her country of
citizenship allows dual
citizenship in some form
or other under the local
laws, is eligible for
registration as Overseas
Citizen of India (OCI).
Minor children of such
person are also eligible
for OCI. However, if the
applicant had ever been a
citizen of Pakistan or
Bangladesh, he/she will
not be eligible for OCI.