Investors watching the PIMCO Total Return exchange traded fund may find a larger mortgage securities position as the bond fund provider rebuilds its mortgage securities position.

Scott Mather, who replaced Bill Gross as one of the managers for the Pimco Total Return Fund (PTTRX), has been buying government-backed bonds and boosted the firm’s total mortgage allocation to 30.3% as of January 31 from 30% back in September, reports Alexis Leonidas for Bloomberg.

“We expect many active alpha opportunities in the mortgage space,” Mather said in the article.

However, the PIMCO Total Return ETF (NYSEArca: BOND), an ETF version of PIMCO’s flagship Total Return Fund (PTTRX), still shows an underweight position to mortgage debt at 19%. Additionally, the ETF has a lower weight toward U.S. government-related debt at 23.0% and a greater tilt toward U.S. corporate debt at 27.0%. [High-Quality, Mortgage-Backed Securities ETF Options]

BOND continues to outperform its mutual fund counterpart. Over the past year, BOND has increased 6.8% while PTTRX rose 4.2%. Year-to-date, BOND is up 1.8% and PTTRX is 1.0% higher.

Before leaving PIMCO, Bill Gross had diminished his mortgage-backed securities exposure, even as agency securities exhibited their best performance last year since 2011.

“They’re moving more neutral, which means they expect agencies to perform better than what the fund’s prior thoughts were,” Todd Rosenbluth, director of mutual-fund research for S&P Capital IQ, said in the article.

Mather, who worked as a mortgage bond specialist at Goldman Sachs Group, said the Total Return Fund had cut MBS allocations in anticipation of lower prices after the Federal Reserve slowed its bond purchasing program and considered hiking interest rates.

“It is relatively unusual for us to own as little agency MBS as we have had,” Mather added. “To some extent we have reduced our underweight by buying select agency mortgages.”

The MBS pick up may have come at an opportune time as mortgage-related debt have been outperforming. According to Bank of America Merrill Lynch data, agency bonds have returned 0.22%, compared to the 0.11% for Treasuries.

For more information on the fixed-income market, visit our bond ETFs category.

Max Chen contributed to this article.