Beijing gets a largely undeserved bad rap over its efforts to claim and develop islands in the South China Sea — the Spratly and Paracel island groups especially. China has long historical links with the area. And the critics forget that in the 1951 San Francisco Peace Treaty between Japan and the Allied Powers, Article 2(f), states: "Japan renounces all right, title and claim to the Spratly Islands and to the Paracel Islands."
This renunciation of the two island groups, and of Taiwan itself, was confirmed in the U.S.-brokered 1952 peace treaty between Japan and the Taiwan-based Republic of China (ROC), then recognized by the United States and Japan as the sole legitimate government of China. So if this meant the ROC had the right to Taiwan then in all logic it also meant the ROC had the right to claim the other islands Japan had renounced in the 1952 treaty — a right which the Beijing-based Peoples Republic of China (PRC) would then normally have been able to claim as a successor government.
The ROC did in fact move to claim the Paracels and until 1950 occupied some of its islands. In 1975 it also claimed sovereignty over all the extensive Spratly island group.