Act of Succession (Denmark)
The 1953 referendum changed the act so that it became possible for a woman to inherit the throne if she has no brothers, a system known as male-preference cognatic preference primogeniture.[2] As the reigning King Frederik IX had three daughters and no sons, this made Princess Margrethe heiress presumptive to the throne, replacing her uncle Prince Knud.[3] Following a referendum in 2009, the Act of Succession was amended so that primogeniture no longer puts males over females, meaning the first-born child would become heir apparent to the throne regardless of sex.The expected result of the referendum was on the balance, since 40% of the entire electorate had to vote yes in order to make the change.[citation needed] The change of the act had no effect on the expected line of succession at the time, but it does affect the line of succession among King Frederik X's younger children, putting Princess Isabella (who was born in 2007) ahead of her younger brother Prince Vincent (born in 2011).