Safes and convertible note are both types of Convertible Securities. Ie they each convert into shares at a future date, usually at a priced round.
A convertible note is structured as debt - there is interest earned until it converts and a maturity date. There are also terms about repaying the debt.
A safe is not debt - it does not have a maturity date and interest does not accrue.
So referring to a "Safe Note" is non-sensical because there is no such thing.
> The safe is just a convertible note with the "event of default," interest, and maturity date provisions stripped out.
> - Carolynn Levy (inventor of the SAFE)
edit ... You could argue it's no longer a convertible note with those provisions taken out, but I'm not sure how much mileage you'd get with that argument.
> It's no longer a "note" when it loses the debt provisions.
You may be right, but what makes you think that?
The common law and some statutory definitions require only that promissory note be, upon breach, reducible to what are called "liquid damages" i.e. "a sum certain in money". This does not mean monetary debt or future payment of money with or without interest. It just means reducible to a certain amount.
The purpose of having a promise with "a sum certain in money" is on the enforcement end. The monetary compensation upon breach (damages) of a promissory note can be unambiguously calculated by a registrar (as opposed to assessment open to interpretation by a judge). This expedites processes such as obtaining summary or default judgment.
However, the promise needn't be in money itself, as long as there is an unambiguous objective calculation of the amount of damages.
I'm not sure how it would be calculable in the case of a note without debt or interest; I'd need to read the note language. If there was nothing specific, one could argue it is portion of the pre-money to the the valuation cap, but that'd be a very loose guess.
A convertible note is structured as debt - there is interest earned until it converts and a maturity date. There are also terms about repaying the debt.
A safe is not debt - it does not have a maturity date and interest does not accrue.
So referring to a "Safe Note" is non-sensical because there is no such thing.