Did you read the description of Sweet Sans? It does a pretty thorough job of answering your questions.

I did, but it didn't answer the questions about Sackers Gothic.

My guess is then that the designer of Sweet Sans had permission to make a derivative of Sackers Gothic based upon the description, I was just curious as to the source of the original specimen.

Which foundry? what designer?

BL

Have you seen Engravers Gothic?
http://new.myfonts.com/search/name%3A(engravers+gothic)/

My guess is then that the designer of Sweet Sans had permission to make a derivative of Sackers Gothic

Why is that? Do you know the origin of Sackers Gothic? I can't seem to find any info on it. In any case, even if Monotype's font was the first engraver-style sans to be digitized doesn't mean it has any special permission from an original designer. In fact, it would be very difficult to find an official source for any typeface in this genre. It was a common, standard style used by many engravers. Something like a sign painter's style or architectural lettering.

Like Marc said, I think the Sweet Sans design description is pretty clear about sources (though I'm biased because I wrote it), but the font maker, Mark van Bronkhorst, should get you any more information if you require it.

I don't have very clear information on this; but, to the best of my knowledge, Gary? Sackers was a stationer who approached a photolettering studio in the fifties or sixties to create a phototype version of the popular 'block' style from engraver masterplates. Allan Haley might know about the transition from Compugraphic to Agfa to Monotype, but my understanding is that a digital version was drawn from the phototype. The Sweets comprise a collection of many different engraving styles as interpreted directly from the plates, including Sweet Sans. So they look quite similar because to some extent they share original sources.