I specifically remember Elon stating that anyone could just use the technology without even informing Tesla, so I looked it up:

https://www.lexology.com/library/detail.aspx?g=ca6c332f-2cc5...

Indeed, there are no documents for executives to sign, but the patents aren't exactly fully free to use either: Tesla promised not to sue any company infringing on its patents as long as they're acting in "good faith," which obviously has a bunch of caveats (one being that you can't sue Tesla over any other patent related issues).

The end result is the same: a decent idea ruined by the lawyers.

> a decent idea ruined by the lawyers.

Or, more cynically, a publicity stunt, facilitated by lawyers. A lot of "look, you can use our patents!" things fall under this umbrella; they're devised in such a way that the company gets some publicity, but no-one can realistically use the patents.

So it was essentially a cross-licensing deal that allowed other automakers to use Tesla charging tech (did this include other Tesla-owned patents?), but the others would effectively have to license their entire patent portfolio to Tesla (can't sue is not too far from a blanket license to use).