Prudential, MetLife shares fall on write-down fears

NEW YORK Oct 20 (Reuters) - The shares of giant life insurers Prudential Financial and MetLife Inc fell on Monday as Goldman Sachs cut its ratings on the companies, citing possible write-downs on investments.

Goldman Sachs, in a research note, cut its rating on Prudential Financial (PRU.N) to "sell" and reduced its 12-month price target on the stock to $40 a share from $58.

Analyst Tom Cholnoky said Prudential's significant exposure to residential and commercial mortgage-backed securities and commercial real estate loans could trigger between $1 billion and $4 billion in impairments -- an amount that could wipe out the insurer's $1 billion in excess capital.

Prudential shares fell 8.26 percent to $38.33 in late morning trading.

Goldman cut MetLife (MET.N) to "neutral" from "buy" and reduced its 12-month target on the stock to $38 a share from $42.

Cholnoky noted that MetLife had raised $2.3 billion in capital, it could still see between $1 billion and $6 billion in losses on assets, denting its $7 billion in excess capital.

MetLife shares fell 2.28 percent to $30.43 in late morning trading on the New York Stock Exchange. (Reporting by Lilla Zuill, editing by Maureen Bavdek)