(Bloomberg) -- While many investors have revived their love affair with corporate bonds this year, one stands out: Pacific Investment Management Co.’s Bill Gross.

His $3.6 billion Total Return exchange-traded fund has more than quadrupled its allocation to such notes since January to more than 41 percent of its holdings. Gross isn’t the only one to find high-grade corporate bonds more appealing lately, given mutual-fund investors have poured $63 billion into the debt this year after pulling record amounts in 2013, according to Wells Fargo & Co. data.

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