Activist investor Trian takes big stakes in Invesco, Janus Henderson

Shareholder activist Trian Fund Management LP has taken big stakes in investment firms Invesco Ltd. and Janus Henderson Group PLC and plans to agitate for deal making aimed at building a rival to the biggest asset managers in the world.

Trian has accumulated 9.9% stakes in both Invesco
IVZ,
-1.40%
  and Janus Henderson
JHG,
-0.55%
 , with the two positions totaling roughly $900 million, people familiar with the matter said.