It does not stipulate that now. When did the law change? What year?
If this is true, then every child born to an out of wedlock mother under the age of 21 (16+5) would not be a citizen at birth. ....Talk about straw grasping.
Go to the below link and you will find this on the 2nd page.
He would fit in this law since he was born in 1961.
4. December 24, 1952 to November 13, 1986 If, at the time of your birth, both your parents were U.S. citizens and at least one had a prior residence in the United States, you automatically acquired U.S. citizenship with no conditions for retaining it.
If only one parent was a U.S. citizen at the time of your birth, that parent must have resided in the United States for at least ten years, at least five of which had to be after the age of 16. There are no conditions placed on retaining this type of citizenship. If your one U.S. citizen parent is your father and you were born outside of marriage, the same rules apply if your father legally legitimated you before your 21st birthday and you were unmarried at the time. If legitimation occurred after November 14, 1986, your father must have established paternity prior to your 18th birthday, either by acknowledgment or by court order, and must have stated in writing that he would support you financially until your 18th birthday.
Now mind you this law is ONLY IF he was born outside the U.S. And if he was born outside the U.S. Obama's mother didn't fit the criteria of 5 yrs after the age of 16 because she was 18 when she gave birth to him.
Also whatever the law is now it was NOT made retroactive.