Oct 1 (Reuters) - Activist investment firm Trian Fund Management LP has taken a 9.9% stake each in asset management firms Invesco Ltd and Janus Henderson Group Plc, totaling about $900 million, people familiar with the matter said.

Trian, founded by Nelson Peltz, Ed Garden and Peter May, has experience in pushing for better returns at asset management companies at a time when many of the smaller players are struggling to stay relevant with giants like Vanguard and BlackRock controlling the bulk of the industry's assets.

The Wall Street Journal first reported the stakes and said they were funded with capital from a long-term portfolio that Trian has built to help facilitate consolidation in the asset management industry.

Representatives for Invesco and Janus Henderson said each company was committed to delivering value for shareholders.

A Janus Henderson spokesman said the firm was informed about the Trian stake on Thursday and that it continues to "make significant progress to increase profitability, drive organic growth, and identify and deliver cost savings."

An Invesco spokeswoman said: "We continuously evaluate opportunities to further strengthen our ability to meet client needs and enhance long-term shareholder value."

Trian could not be reached for comment.

The asset management industry has been shaped by a recent wave of consolidation as investors prefer to put money into cheaper index funds instead of more expensive actively managed portfolios.

Earlier this year, Franklin Resources, known for its Franklin Income Fund, bought rival Legg Mason, where Trian had invested for the second time in early 2019.

Invesco bought OppenheimerFunds last year.

Trian often wins board seats at its target companies and had seats on the Legg Mason board. It has previously owned stakes in Bank of New York Mellon and State Street and recently announced a stake in cable giant Comcast Corp , saying its stock was undervalued. (Reporting by Svea Herbst-Bayliss in Boston and Praveen Paramasivam in Bengaluru; Editing by Rashmi Aich and Ana Nicolaci da Costa)