Bildt had said at the end of October that he would sell the options after fierce criticism from Swedish media, political opponents and commentators pointing out a potential for a conflict of interest for a foreign minister of a European Union country.
The minister sold his shares in Vostok Nafta in October.
But on Friday, Bildt continued on Friday to hold 6,000 shares in Lundin Petroleum, a Swedish oil company that has operations in Sudan. His stake was worth 436,500 kronor, according to a Swedish government list obtained by AFP.
In November US-based group Human Rights Watch criticised Bildt for his stake in Lundin Petroleum, which is suspected of having close ties to the government of Sudan, a country criticised for its human rights record.
Bildt, 57, has holdings in about 30 companies and investment funds valued at about 1.69 million euros, according to a calculation by AFP.