During the long, tech-driven bull market, you may have seen more than one article suggesting Berkshire Hathaway CEO Warren Buffett's investing style was no longer valid.
### Instruction: What is the sentiment of this news? Please choose an answer from {negative/neutral/positive}
### Input: During the long, tech-driven bull market, you may have seen more than one article suggesting Berkshire Hathaway CEO Warren Buffett's investing style was no longer valid.
### Response: mildly negative