Skywald Comics was a short-lived comic book company that went into business in 1970 and out in 1975. It was an alliance between Sol Brodsky (former production manager and occasional artist for Marvel) and Israel Waldman, a publisher specializing in low-budget periodicals including (at times) comic books. Waldman's main venture into comics previously has been with a company called variously I.W. Publications, Super Comics and I think some other names. To quote Wikipedia, they issued "…in the late 1950s and early 1960s…unauthorized comic book reprints for sale through grocery and discount stores."
Brodsky had had a major falling-out with Marvel publisher Martin Goodman and left the company. He teamed up with Waldman, they published some comics (mostly on the cheap) then Brodsky pulled out and returned to Marvel after Goodman left.
And now, following up on my follow-up to this question, Rob Allen asks…
Following up on your post about why Jack never worked for Western, I wonder about another path not taken.
Did Jack consider joining Sol Brodsky in his new venture with Israel Waldman? It seems likely that Skywald couldn't afford Jack's page rate, but if they could, the possibilities seem enticing. I think the Fourth World would have sold better than the Western comics that Skywald did produce. And Skywald had more success than DC in black & white magazines. Jack and Sol left Marvel almost simultaneously; did they talk to each other about their plans?
Nope. They weren't quite as simultaneous as that in their departures and Jack probably wouldn't have left without an offer than would pay him as well or better…which, as you note, Skywald was unlikely to do. There was also something chintzy and crooked about the company and Jack didn't like that, which is why he rejected the occasional suggestions of Steve Ditko that he work for Charlton.
Simon and Kirby had briefly done some work through Charlton and had never been paid-in-full. Jack once said of that company something like, "The guys who run it don't belong in comics…or anywhere that's not a prison." That's an approximate quote. He liked Sol Brodsky but Sol never made an offer and Jack recalled how Waldman had reprinted Simon & Kirby material without their permission.
Just to head off further questions about other companies then publishing comics: I don't think there was anyone besides DC and Marvel that had the stability and the budgets that Jack felt were mandatory. He either didn't trust other publishers because of past dealings or knew they weren't interested in the kind of material he did or just knew (roughly) their page rates. He was approached by a few different people who wanted to get into the business but none of them seemed to have the start-up capital, an understanding of the industry or the connections to get decent distribution.
He'd also heard stories from Wally Wood about how he (Wood) believed Tower Comics had been sabotaged. Going with an unestablished publisher was not a gamble Jack was prepared to take. In a very real sense, he was trapped working for DC or Marvel…and I don't think either one treated him very well. Maybe they would have later but not then.