Are my strategies private when I backtest them online?

On our platform, yes by default: strategies you build are visible only to your account, backtest results are private unless you explicitly enable a public share link, and publishing to the marketplace is an explicit opt-in action. We don't trade, resell or train on your rule sets.

The general-web caveat: this varies by platform, and it's a fair question to ask any vendor directly. Look for an explicit statement about strategy ownership and whether shared links are opt-in — silence on the topic is an answer too.