The Social Security System (SSS) joined the sell-down of Philex Mining shares last month.
SSS offloaded 20.47 million PX shares at a price range of P3.26 to P3.58 from August 1 to 31.
PX plunged to a 52-week low of P3.08 in late August as investors fled the stock following the soft demand for its stock rights offering.
It has lost more than half of its value since hitting a 52-week high of P6.66 in March this year.
SSS subscribed to a total of P533 million (169.186 million shares at P3.15 each) in the SRO.
The state-run pension fund is the second biggest PX shareholder with a 19.74 percent share worth P3.6 billion after the Metro Pacific group led by bilyonaryo Manny V. Pangilinan.