Sandisk (NASDAQ:SNDK) gave investors two pieces of news on Thursday, Oct. 29. The flash memory company’s fiscal first-quarter revenue grew 23% over the previous quarter to $11.0 billion. And the board approved an eight-for-one stock split, with split-adjusted trading expected to start Friday, Nov. 20. Does a split announcement tell investors anything about where a stock heads next? I checked what happened over the year after eight big-name split announcements, measured from every stock’s close on announcement day. Missed Nvidia in 2009? This Rare Signal Is Flashing Again. In 2009, a “Double Down” signal flashed for a little-known chipmaker called Nvidia. For the first time in years, that same “Total Conviction” signal is flashing for a company 1/100th the size of Nvidia. Continue » Five of the eight were up one year later, and the median stock rose around 26%. Five also beat the S&P 500. But the results ran from a 43% drop to a 79% gain. Image source: Getty Images. Eight splits, five gains Apple announced its split on July 30, 2020. Nvidia announced one on May 21, 2021, and another on May 22, 2024. Alphabet followed on Feb. 1, 2022, and Amazon on March 9, 2022. Walmart announced its split on Jan. 30, 2024, Broadcom on June 12, 2024, and Netflix on Oct. 30, 2025. Walmart did best, with its stock up around 79% in the next year. Broadcom climbed about 71%, and Apple gained 52%. Nvidia rose 40% after its 2024 announcement and a smaller 11% after its 2021 one, but that smaller gain still beat an S&P 500 that dropped in the same 12 months. Alphabet lost around 27% and Amazon about 34%. Netflix is down about 43% as I write, a day shy of its full year. These are price-only numbers, adjusted for the