[lohankin]

The target acceptance rate was rumored to be 2% - which roughly corresponded to the percentage of Jewish population in USSR. I was one of those Jewish applicants in 1973 :) Exam was conducted in a separate room. When in doubt, the criteria for identifying Jews among all applicants was funny (in retrospect): they tried to guess by the last name. But some names are more "typical" than others, so the criteria was not 100% accurate. They preferred to err on the side of caution, and some perfectly Russian people were put in the same exam room with the Jews. This is my recollection.

[forapurpose]

> they tried to guess by the last name

You'll find this interesting:

https://news.ycombinator.com/item?id=15424769

[lohankin]

Those cases were probably quite common. From wikipedia article about Glenn Gould, the great Canadian pianist: "The family's surname was changed to Gould informally around 1939 in order to avoid being mistaken for Jewish, given the prevailing anti-Semitism of prewar Toronto and the Gold surname's Jewish association"