Hope nobody gets angry for refreshing an old thread, but given it was in English, that was very helpful for me as an expat.
I'm living and working in Germany for some years, pay my tax here, do my Steuererklärung, usual stuff. I'm from another EU country (EU nationality), in case that'd be important.
I'm still not sure regarding the altcoins.
Case A) Let's say I buy BTC mit EUR today (February 2016), and immediately buy an altcoin with them. I keep them in a safe (coldwallet) and eventually cash them back to BTC in, let's say November 2016. Ideally I'll have quite some more BTCs than at the beginning. When can I cash them back to EUR free of tax? Still February 2017 or November 2017?
Case B) Similar to B, but instead of keeping the altcoin safe in a coldwallet, I'm trading with them for months long. Eventually converting to/from BTC/altcoin(s) back and forth. In November 2016 I decide I've won/lost enough and want to trade back to EUR. Which date would make this taxfree? February or November 2017?
And last but not least. I understand that even this being "taxfree", I have to provide all my public BTC addresses to the Finanzamt... Do I have to provide them with the information of the altcoin trader as well? Is that one easy to get?
Many thanks in advance and I hope the answer can be useful for more people.
I can understand some German, but the answer in this thread wasn't clear enough for me:
https://bitcointalk.org/index.php?topic=612741.0