From "Technology Importation, Corporate Strategies, and the Rise of the Japanese Semiconductor Industry in the 1950s" at https://muse.jhu.edu/article/256067/pdf
> In March 1952, Ibuka traveled to the United States to investigate its domestic tape-recorder market and to learn from American firms. It was during this trip that Ibuka ran across a WE newsletter announcing that AT&T was openly licensing its transistor patents for a nominal licensing fee of $25,000. Literally overnight, he decided that transistor radios should be Sony’s next major product. ... Iwama and Tsukamoto, along with three other researchers, officially began Sony’s transistor-development project in July 1953, just months before the company signed a patent-licensing agreement with AT&T (Sony Corporation, 1986, p. 325).
(If that is not accessible, https://project.iss.u-tokyo.ac.jp/kikkawa/iss-6.pdf says Sony "Concludes transistor license agreement with Western Electric" in October 1953. Western Electric was "the primary equipment manufacturer, supplier, and purchasing agent for the Bell System from 1881 until 1984" says https://en.wikipedia.org/wiki/Western_Electric).
https://en.wikipedia.org/wiki/Transistor points out AT&T "first used transistors in telecommunications equipment in the No. 4A Toll Crossbar Switching System in 1953" and "The first prototype pocket transistor radio was shown ... from August 29 to September 6, 1953."
A quick look of publications of the time finds articles like this August 1952 piece from the Illinois Business Review :
> The Electronic Department of the General Electric Company reports that a whole new electronics business is growing out of the development of the transistor, said to be a potential successor to the vacuum tube. Transistors are made of germanium, which is recovered as a byproduct in the smelting and refining of zinc ores. Since they contain no heated element they never “burn out” and last indefinitely. The giant digital computers, or magic brains, which now use several thousand vacuum tubes and occupy a large-size room can conceivably become small enough to be applied to everyday business and industrial problems as are comptometers. Most of the telephone, industrial control, and business machine applications can be filled by the transistor; it will become practical to build amplifiers for use on transoceanic telephone cables. The simplicity and ruggedness of the transistor will have a direct effect also on military electronics, especially on airborne equipment.
or this October 1952 article on some of the uses of transistors - https://archive.org/details/bub_gb_iSEDAAAAMBAJ/page/n137/mo... with the subtitle "look for them soon in pocket radios and TVs almost that small" and the comment " RCA has just announced that it has boosted the frequency of several units high enough for use in FM radios and TV sets."
If you don't mind the high noise, the same 1952 issue includes a description of how you can build your own transistor radio, at https://archive.org/details/bub_gb_iSEDAAAAMBAJ/page/n239/mo... .
Hard to think Western Electric didn't know of any of these possibilities when discussing licensing with Sony.