Earlier today Poloniex sent out a message to all users that they were going to de-list 27 Altcoins on Sept. 5, 2016. As they only list around 100 coins, that is nearly a quarter of the coins listed on the exchange.
Most of the altcoins listed have dropped in value, with the average around 40%. Some coins have rebounded, only to have fallen deeper into the abyss.
The coins dropped by Poloniex appear to be zombie coins, basically dead coins that continue to live on exchanges and coming to life when traders "pump and dump" them. Some of the coins, such as FIBRE, XPB, and others have jumped in price 1000% in minutes only to be dumped and leaving traders holding bags of worthless coins during the pumping and dumping. Poloniex has made a terrible decision in dumping so many coins all at once because such a move is affecting the entire market.
The coins to be delisted are: ABY, ADN, BITUSD, CNMT, DAO, FIBRE, FLT, GAP, GRS, HYP, IFC, LQD, MCN, MINT, MMC, MNTA, PIGGY, SILK, SWARM, WDC, XC, XCR, XPB, XUSD, YACC.
I plan to dump zombie coin investment monies into STEEM. This strategy will definitely benefit any coin portfolio in the long-term due to the stability -- and usage --- of the coin.