The Pimco Total Return Fund, the world's largest bond fund, cut its holdings of mortgages in February to 29 percent from 36 percent in January, data from the firm's website showed on Tuesday.
The fund, which has $236 billion in assets and is managed by Pimco co-founder and co-chief investment officer Bill Gross, also cut its U.S. government-related holdings to 43 percent in February from 46 percent in January.
(Read more: US investors closely monitoring Pimco after internal strife)
The fund increased its holdings of non-U.S. developed market securities, to 9 percent in February from 7 percent in January. The fund cut its effective duration to 4.71 years in February from 5.05 years.
Pacific Investment Management, a unit of European financial services company Allianz SE, had $1.91 trillion in assets as of December 31, according to the firm's website.