Both coins have been around a long time. It just so happens Yacc was added to a major exchange long before Yac. That doesn't make it a scam. The implication that they intentionally stole the name/ticker symbol to scam people is ridiculous and does nothing to further your cause. If you think there is market confusion pressure Yacc to change their name or you should change yours. This is simply a simple name dispute between private parties. Putting it on Poloniex is just passing the buck. It's not their job to play judge and jury.
OK, you seem a rational person, so let's try this...
Yacoin, released in May of 2013 is the:
THIRD Proof of Stake coin released.
FIRST to introduce Scrypt-N, NFactor, scrypt-jane, etc.
FIRST to implement sha3
Has been on major exchanges since May of 2013.
Yacoin initial announcement
https://bitcointalksearch.org/topic/annyac-yacoin-yet-another-altcoin-start-is-now-196196 : 177 Pages : Read 301977 times
Yacoin ongoing development
https://bitcointalksearch.org/topic/annyac-yacoin-ongoing-development-206577 : 165 Pages : Read 291358 times
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Now on to YaCCoin...
Released January, 2014
Openly created using
http://devtome.com/doku.php?id=scrypt_altcoin_cloning_guide (
https://github.com/yaccoin/yaccoin/commit/c874a622616488ad599b4f577b0b1646e5b33168)
Introduced nothing new to the crypto community, outside of a great name attack on an older established coin.
YaCCoin initial announcement
https://bitcointalksearch.org/topic/yaccoin-up-running-and-stable-482232 : 1 Page : Read 2189 times
Do a search... any search engine, for YaCCoin... do you get a "did you mean" suggestion, and/or do you see many relevant pages for YaCCoin, or Yacoin?
Now... With the facts stated above, do you think it's safe to assume that Poloniex ACCIDENTALLY listed the wrong coin, or was the intent to actually list Yacoin ?