Online resources refer to him as Jacob “Jacques” Schulman, and John Spring, in his 2009 book on ancient coin auction catalogs, calls the founder “the first Jacques Schulman.” In fact, according to Laurens, his name was simply Jacob. Jacques, Laurens’s father, came later.

True, his name was Jacob (???? = Ya?aqov), but in Amsterdam personal names were typically translated into French. Hence, Jacob is Jacques. In the nineteenth century every numismatic publication and advertisement I have read about him and his business only refer to him as Jacques, never Jacob. I found his name as Jacob only in original birth records.

This reminds me of the confusion back in 2002 regarding the so-called James Ossuary purportedly discovered by Oded Golan, and the name James, where some called him Jacob. I published a lengthy list on original Synoptic-L (now defunct) giving dozens of equivalents in other languages so that researchers would not be confused or vexed when encountering the subject published in other languages.

Apologies to David Hill for not recalling his 2017 article and citing it. My online article on the Schulmans was actually written between 2011-2014, and only recently updated the week prior to its first appearance in The E-Sylum, based on my old unpublished notes. I will make additions based on David Hill's article when time allows crediting him for his fine work.

While I can't add anything regarding the Schulmans, this question brings us close to the "translation of names" thread of a week or two back. My wife's father was Dutch, and was variously known as Jacobus, Jacques or Sjaak, depending on which way the wind was blowing. And when he got to New Zealand, "Jack" was much easier for everyone.

"Hans" complicates things - Hans Schulman may have been a different guy, but then Hans is often short for Johann/Johannes (John), which gets us back to Jack again. (Before anyone points it out, I know Jacobus/Jacques maps to James rather than John in English.) But I'll stop there and get myself a drink!

The "Vincent" referred to would be Vincent Del Grosso, who worked for Hans in the 1970s, possibly earlier.

The imputation that there were two J. Schulman firms is misleading. In 1980 a 100th Anniversary auction was conducted. (I was the only American who crossed the ocean to attend. It was my first trip to Europe.) It is common for old numismatic firms to celebrate their antiquity. Henry Christensen Inc had a 150th Anniversary auction; the catalog intro did admit that they were ships' chandlers for much of that history. Spink date themselves to 1666, but I've never learned what they did before, say, 1885. Stack's, on the other hand, claim to go back to 1935, but I am confident they are older, probably going back to 1919 in coins and stamps, in New York City.