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.