The Singapore group welcomed the move and said it was ready to explore prospects for further collaboration with Asia's largest bourse.
The TSE said it had purchased 53.
051 million shares in Singapore Exchange Limited (SGX), or about 4.99 percent of its issued share capital.
The purchase has a value of about 528 million Singapore dollars (342 million US dollars) based on SGX's closing share price of 9.
95 Singapore dollars, up 1.5 percent on the day.
The TSE said that "for the time being" it had no intention to raise its stake in SGX to more than five percent.
"TSE initiated this purchase recognising the importance of having closer collaboration with SGX," the Tokyo bourse said.
The TSE agreed in December to reinforce ties with the Singapore exchange operator by licensing TOPIX-related indices to SGX to create derivatives and exchange traded fund products for trading on SGX.
The two bourses will also explore the establishment of a trading and clearing link for both derivative