Long only is a feature or policy of many mutual funds, it refers to a policy of only holding "long" positions in assets and securities. To be "long" an asset, derivative or security means being a buyer, generally one who benefits from an increase in prices; the opposite is to be "short" which means the holder of the short position gains profits when the prices decrease. A long only strategy is predicated on positive performance of the prices of the assets that are held e.g. in the case of equities a long only strategy will do well during a bull market, but will likely not do well during a bear market.
Synonyms: Long only fund, Long only strategy
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