Earlier quoted context omitted.
>There is no debt involved Can you provide an executed contract to confirm? YC appears to have moved away from convertible notes (ie. debt) [1], but if you read closely it appears that PG said the reason was to avoid debt term limits and interest rate limits....so it's an even more extreme version of debt, just not 'debt' according to CA regulations. [1] http://blog.ycombinator.com/announcing-the-safe-a-replacemen...
If you read that link you posted you'll see "what the investor buys is not debt, but something more like a warrant. So there is no need to fix a term or decide on an interest rate" Warrants just give the investor the right to purchase equity at a given price some time. They are not debt.
No matter what it's called: loan, debt, warrant, convertible note, SAFE, it's an instrument that attaches to future earnings.