On sec.gov, I can't find any form that shows Berkshire Hathaway purchased a massive amount of stock shares from Alphabet

I know it hit the news everywhere a few days ago and I wanted to actually see the report/form. I went on [sec.gov](http://sec.gov), went to both Alphabet and Berkshire Hathaway's sections and read all the recent form 114, 3, and 4. Couldn't find any report showing Berkshire Hathaway bought those shares from Alphabet. Where can I find the "official" reports? I want to develop a habit of confirming things like this instead of just relying on the news all the time.