Just caught something worth paying attention to. Over the last 13 quarters, Berkshire Hathaway has been selling way more stock than buying - we're talking $187 billion in net sales. That's a pretty loud signal from Warren Buffett and his team that they're struggling to find decent entry points in this market.

Think about it. Buffett used to say finding months where they weren't net buyers was rare. Now? They're net sellers quarter after quarter, even with over $300 billion sitting in cash. They've picked up some positions in companies like Alphabet and UnitedHealth Group, but they're still selling overall. That doesn't happen for no reason.

Here's where it gets interesting though. The S&P 500's CAPE ratio hit 39.8 recently - that's cyclically adjusted price-to-earnings for those not familiar. Only time we've seen that before (outside the last few months) was right before the dot-com crash in 2000. We're talking about only 26 months out of 829 total months where the index hit that level.

So what happens historically when CAPE goes above 39? The data is pretty clear. Average returns are flat over 6 months, negative 4% over a year, down 20% over two years, and down 30% over three years. If that pattern holds, we're looking at significant downside through 2029.

Now, there's the counterargument - AI could drive earnings higher faster than expected, which would bring valuations back in line. That's possible. But Warren Buffett's $187 billion warning shouldn't be ignored lightly. The guy didn't build that track record by accident.

The practical takeaway? Be selective. Only hold stocks you'd be comfortable keeping through a real downturn. And if you're buying, focus on companies with reasonable valuations and earnings that should be meaningfully higher in five years. Buffett's basically telling us that's the bar right now.