http://whirtorrgetftvz4g466sjqkegtyi35bjl4bvotfkfossunf5my4x6ad.onion/blog/bitcoin-privacy
Source: River.com And while this creates two new addresses, if the observer of the blockchain, such as a chain analysis company that we will talk about more later, knew that Alice had 1.2 BTC before, they know that one of those outputs is probably hers. This can be deduced through applying heuristics and some logic on top of how Bitcoin works.