I had purchased Quark worth BTC0.10 in 2014. Lost almost the entire investment, after the coins became almost worthless. Sold all my coins in Vircurex, at almost 95% loss. These guys should not be allowed to cheat the users again.
Unfortunately these scam guys hop from one coin to another coin.
Last pump and dump from (part of) this same scam team was chaincoin.
If it is quiet now at Quark, then they cheat users with other coins.
I summarized some of the (Quark) scammers work (and therefore potential pump and dump coins) here:
https://bitcointalk.org/index.php?topic=1966967.msg19562300#msg19562300