It was bloody obvious to anyone who didn't choose to actively look away.
Witold Pilecki, quite possibly the bravest man I ever read about, went under cover to Auschwitz in 1940.
His Polish resistance network - ZOW - first started forwarding reports into the holocaust at Auschwitz Birchenau to the Polish government in London in March 1941. He was the main source of information on the holocaust in the early war, which was shared with all allies.
His landmark report produced after escaping from several years under cover in Auschwitz as an inmate was produced in 1943[1]. He'd also organised a resistance network within the camp, and regularly smuggled information out to ZOW during his time there.
Earlier? It was well known what Germany was doing well before the war (no apology for copy pasting a few snippets direct from Wikipedia):
Germany passed the sterilisation and euthanasia laws in 1933, with Action T4[2]
California eugenics leader returned to the US from Germany in 1934, talking of the fine program that existed in Germany, when Germany was forcibly sterilising 5,000 a month.[3]
Eugenics researcher Harry H. Laughlin often bragged that his Model Eugenic Sterilization laws had been implemented in the 1935 Nuremberg racial hygiene laws[3]
The forced sterilization program engineered by the Nazis was partly inspired by California's.[4]
The Rockefeller Institute funded Mengele before he went to Auschwitz.
Not forgetting the many refuges that found their way to British, American, Canadian and other shores in the years leading up to 1939. Many of whom would have been able to report exactly what was going on before war broke out.
Worth noting that Harry Laughlin was not an outlier. Many of the 'great and the good' at that time were supporters of eugenics and included Winston Churchill, GB Shaw, Neville Chamberlain, JM Keynes, Jack London and HL Mencken. Denmark, Sweden, Norway, and Finland all brought in eugenics laws in the 1930s. Those deemed to be unfit to reproduce were sterilized.
https://www.economist.com/europe/1997/08/28/here-of-all-plac...
Oh it wasn't in isolation - a lot of well known names in many nations had an interest, and there was varying degree of popular interest too. It seemed particularly popular in the Nordic nations, and America. The were eugenics societies in most of the major nations. America had popular societies in many states, it was in the media, and the US were among the earliest to bring in eugenic laws - and the last to keep them around.
So in the context of OP's comment it seems very unlikely that many were completely unaware of what Germany was doing along similar lines, and going so much further. Whether that was still viewed as OK in the context of the time - a time before the holocaust - is of course far harder to judge.
And the U.S., via its isolationist policy at the time, largely chose to just stay out of a war which was being fought "way over there" and which we had no direct interest in at the time. But then the Japanese attacked Pearl Harbor in late 1941, which changed everything. This is when IBM's direct involvement with Germany also ended.
Yes Pearl Harbor changed everything, yet nothing changed. Direct dealing would be illegal, so they simply relayed via IBM Geneva. The book made a convincing case that IBM, and Watson himself continued to deal - and profit - throughout the war. "IBM's direct involvement with Germany ended" is pretty academic if they just started funnelling through a subsidiary.
Well, don't forget that the name "Watson" applies to both Watson Sr. (who founded IBM but who had a somewhat less than stellar reputation, at least at first) and his son Watson Jr., who ran IBM himself for a great many years and who had a much better reputation. Apparently father and son didn't really get along too well, though.
Witold Pilecki, quite possibly the bravest man I ever read about, went under cover to Auschwitz in 1940. His Polish resistance network - ZOW - first started forwarding reports into the holocaust at Auschwitz Birchenau to the Polish government in London in March 1941. He was the main source of information on the holocaust in the early war, which was shared with all allies.
His landmark report produced after escaping from several years under cover in Auschwitz as an inmate was produced in 1943[1]. He'd also organised a resistance network within the camp, and regularly smuggled information out to ZOW during his time there.
Earlier? It was well known what Germany was doing well before the war (no apology for copy pasting a few snippets direct from Wikipedia):
Germany passed the sterilisation and euthanasia laws in 1933, with Action T4[2]
California eugenics leader returned to the US from Germany in 1934, talking of the fine program that existed in Germany, when Germany was forcibly sterilising 5,000 a month.[3]
Eugenics researcher Harry H. Laughlin often bragged that his Model Eugenic Sterilization laws had been implemented in the 1935 Nuremberg racial hygiene laws[3]
The forced sterilization program engineered by the Nazis was partly inspired by California's.[4]
The Rockefeller Institute funded Mengele before he went to Auschwitz.
Not forgetting the many refuges that found their way to British, American, Canadian and other shores in the years leading up to 1939. Many of whom would have been able to report exactly what was going on before war broke out.
[1] https://en.wikipedia.org/wiki/Witold's_Report
[2] https://en.wikipedia.org/wiki/Aktion_T4
[3] https://en.wikipedia.org/wiki/Nazi_eugenics
[4] https://books.google.com/books?id=1lvbUy441m0C&pg=PA18