A child born outside India between 26.01.1950 and 09.12.1992 shall be a citizen of India by descent, if the father of the child was an Indian citizen by birth at the time of the birth of the child. In case the father of child was an Indian citizen by descent at the time of the birth of the child, the child shall not be a citizen of India by birth, unless the birth of the child is registered with the concerned Indian Mission abroad within one year of the birth. Approval of the Central Government is necessary in all such cases where the request for such registration is made after the expiry of the said period.

A child born outside India between 10.12.1992 and 02.12.2004 shall be a citizen of India by descent, if either of the parents (father or mother) was an Indian citizen by birth at the time of birth of the child. In case either of the parents of child was an Indian citizen by descent at the time of the birth of the child, the child shall not be a citizen of India by birth, unless the birth of the child is registered with the concerned Indian Mission abroad within one year of the birth. Approval of the Central Government is necessary in all such cases where the request for such registration is made after the expiry of the said period.

A child born outside India on or after 03.12.2004 shall be a citizen of India by descent, if either of the parents (father or mother) is an Indian citizen at the time of birth of the child and the birth of the child has been registered with the concerned Indian Mission abroad within one year of the birth and the parents of the child have to submit a declaration that the child does not hold passport of another country. Approval of the Central Government is necessary in all such cases where the request for such registration is made after the expiry of the said period.

Descent (Section 4)

person born outside India on or after 10th December 1992 but before 3rd December, 2004, is considered as a citizen of India if either of his parents was a citizen of India by birth at the time of his birth. 

2)in your case your son was born in 2001 in Singapore and would be citizen by descent 

2)  

Procedure
Application for registration of the birth of a minor child to an Indian consulate under Section 4(1) shall be made in Form-I and shall be accompanied by an undertaking in writing from the parents of such minor child that he does not hold the passport of another country.

3) in your case your son birth was not registered with Indian consulate in Singapore and he is holding Singapore passport 

3) By Registration (Section 5(1))

Indian Citizenship by registration can be acquired (not illegal migrant) by: -

Application for Indianan citizenship can be made 

Persona of full age whose both parents are registered as citizens of India under section 5(1)(a) or section 6(1) can acquire Indian citizenship under section 5(1)(e).

1. Son born in Singapore becomes a citizen of Singapore and hence was granted a Singapore passport (this is irrespective of being an Indian descent person)

2. You can apply to the Indian Consulate in USA /Singapore, for Indian Citizenship, by undertaking to permanently relinquish the Citizenship of Singapore, by providing cogent /justifiable reasons for the purposes. This is not an usual thing and can be processed easily.

1. Yes, he is Indian origin bu birth and hence he can apply for PIO or OCI card from india.

2. Sine he does not appeqr to have such card as yet , he must get those before relinquishing his Singapore nationality and apply for citizenship of India. 

Foreigners Division

Acquisition of Indian Citizenship (IC)

Indian citizenship can be acquired by birth, descent, registration and naturalization. The conditions and procedure for acquisition of Indian citizenship as per the provision of the Citizenship Act, 1955 are given below:

(1) By Birth (Section 3)

• A person born in India on or after 26th January 1950 but before 1st July, 1987 is citizen of India by birth irrespective of the nationality of his parents.

• A person born in India on or after 1st July,1987 but before 3rd December, 2004 is
  considered citizen of India by birth if either of his parents is a citizen of India at the time of his birth.

• A person born in India on or after 3rd December, 2004 is considered citizen of India by birth if both the parents are citizens of India or one of the parents is a citizen of India and the other is not an illegal migrant at the time of his birth.
  
  An ?illegal migrant? as defined in section 2(1)(b) of the Act is a foreigner who entered India.
  
  (i) without a valid passport or other prescribed travel documents : or
  
  (ii) with a valid passport or other prescribed travel documents but remains in India beyond the permitted period of time.

(2) By Descent (Section 4)

• A person born outside India on or after 26th January 1950 but before 10th December 1992
  is a citizen of India by descent, if his father was a citizen of India by birth at the time of his birth. In case the father was a citizen of India by descent only, that person shall not be a citizen of India, unless his birth is registered at an Indian Consulate within one year from the date of birth or with the permission of the Central Government, after the expiry of the said period.

• A person born outside India on or after 10th December 1992 but before 3rd December, 2004, is considered as a citizen of India if either of his parents was a citizen of India by birth at the time of his birth. In case either of the parents was a citizen of India by descent, that person shall not be a citizen of India, unless his birth is registered at an Indian Consulate within one year from the date of birth or with the permission of the Central Government, after the expiry of the said period.

• A person born outside India on or after 3rd Decmber, 2004 shall not be a citizen of India, unless the parents declare that the minor does not hold passport of another country and his birth is registered at an Indian consulate within one year of the date of birth or with the permission of the Central Government, after the expiry of the said period.

Procedure
Application for registration of the birth of a minor child to an Indian consulate under Section 4(1) shall be made in Form-I and shall be accompanied by an undertaking in writing from the parents of such minor child that he does not hold the passport of another country.

By Registration (Section 5(1))

Persons of full age and capacity who has been registered as an OVERSEAS CITIZEN OF INDIA (OCI) for five years and residing in India for ONE YEAR before making application under section 5(1)(g). Application shall be made in Form III-C.

Clarification: A person shall be deemed to be a Person of Indian origin if he, or either of his parents, was born in undivided India or in such other territory which became part of India after the 15th day of August, 1947.

1. Your child is citizen by descent.

2. The birth of child in such case has to be registered with the Indian consulate.

In case birth is not registered he has to apply for citizenship by registration and waive his singapor citizenship.

You can go through the procedures as laid down in the application for passport  itself to comply with the requirements for applying for passport for your son as per law.

Where your son was born ? Till 18 years he is dual citizen and on becoming major have to choose one citizenship. For Indian passport, he needs to be in India and have Indian I`d. Approach Indian consulate for precise information.

His citizenship is Indian by descent.

person born outside India shall be a citizen of India by descent if both the parents or either of them is an Indian citizen..

A child Born to Indian parents may claim his Indian citizenship at any time. In case your son wants surrender Singapore passport then he can apply for indian passport after taking the NOC from the singapore government.

1. Your son is an Overseas Citizen of India but not an India Citizen.

2. Having been born in Singapore, he is the natural citizen of Singapore. For getting Indian passport your son shall have to become Indian Citizen as per Indian Citizenship Act. he is required to stay in India for a period of 11 years for claiming Indian Citizenship. 

1. It is to be understood that he is already a citizen of Singapore.

2. After coming to India with his Singapore passport, if he applies for Indian passport, his birth certificate will show that he is born at Singapore for which his passport application will be rejected.

1. No your son cannot clai Indian citizenship as India doesn't allow dual citizenship.

2. He have to give up citizenship of singapore before he can apply for citizenship of India before applying for Indian citizenship on ground of citizenship on descent.

Dear Sir,

Yes, A person born outside India on or after January 26, 1950 is a citizen of India by descent if his/her father was a citizen of India by birth. A person born outside India on or after December 10, 1992, but before December 3, 2004 if either of his/her parent was a citizen of India by birth.

It doesn’t matter if it’s only one parent or both parents who have Indian citizenship. According to India’s Citizenship Act, as long as at least one parent has Indian citizenship at the time of the child’s birth, and the child is registered at an Indian consulate within one year of birth, with the declaration that the child does not have a foreign passport, the child is an Indian citizen by descent.

4. Citizenship by descent.— (1) A person born outside India shall be a citizen of India by descent,—

 
 (b) on or after the 10th day of December,1992, if either of his parents is a citizen of India at the time of his birth:

Provided also that on or after the commencement of the Citizenship (Amendment) Act, 2003, a person shall not be a citizen of India by virtue of this section, unless his birth is registered at an Indian consulate in such form and in such manner, as may be prescribed,—
 
 (i) within one year of its occurrence or the commencement of the Citizenship (Amendment) Act, 2003, whichever is later; or
 
 (ii) with the permission of the Central Government, after the expiry of the said period:
 
 Provided also that no such birth shall be registered unless the parents of such person declare, in such form and in such manner as may be prescribed, that the minor does not hold the passport of another country.

He was only born in Singapore and tha tg is why he was given a Singapore passport but only till he is 18. After he turns 18 he can renew it or not and he may opt for Indian citizenship. It is an easy process.

yes by descent he is an Indian citizen and therefore the process is to renounce the Singapore passport and come back to India.

If he has Singapore passport naturally issued as he was a citizen by birth in Singapore. Now he has to apply to Indian passport and be a  Indian citizen. He can apply for Indian passport as his parents have Indian origin