Invesco Ltd. wants to start a new type of exchange-traded fund that conceals its portfolio.

The actively-managed ETFs would rely on Invesco’s own proprietary design, according to regulatory filings from the $1.2 trillion money manager. Unlike conventional ETFs, which mostly track an index and publish a full list of assets every day, these funds would keep some of their holdings hidden to protect their strategies from copycats.

It’s all part of a growing push among active managers to counter an exodus of cash from their mutual funds. Stock pickers have largely steered clear of ETFs, fearing that the daily disclosure they require could compromise their secret sauce and facilitate front-running. But earlier this year, the Securities and Exchange Commission approved some less-transparent funds, prompting asset managers to take another look.

“We want to make sure that for our clients we’re offering all possibilities for them to build better portfolios,” Dan Draper, Invesco’s global head of ETFs, said in an interview. “This is really a chance for us to look at everything that has been filed in the non-transparent, active space and we really felt that there were some key ingredients that were missing.”

The Atlanta-based company, already the fourth-largest U.S. ETF issuer with $206 billion, has aggressively expanded both its active and passive capabilities in recent years. The firm bought Guggenheim Investments’ ETF business in 2018, as well as OppenheimerFunds in May.

Under the proposed structure, funds will conceal a portion of their assets and instead publish a list of securities that’s highly correlated to the performance of the portfolio, and provide an indicative snapshot of the portfolio’s value at intervals throughout the trading day.

This information could be used by traders, known as market makers, to keep the price of the ETF in line with its value. Traders will also be able to create and destroy shares in the fund at least twice a day, via an Invesco-affiliated broker-dealer, instead of waiting until markets close.

The first funds will focus on U.S. equities, global stocks and fixed income, the filings show.

Invesco hasn’t yet decided whether it will look to license its design to other asset managers if it gets approval, and may still choose to start funds using some of the other existing and prospective non-transparent structures, Draper said. Fidelity Investments, T. Rowe Price Group Inc., the New York Stock Exchange and Blue Tractor Group are all seeking approval for alternative models. Precidian Investments secured approval for its wrapper in May.

This article was provided by Bloomberg News.