Alphabet Inc. (NASDAQ:GOOGL) and Facebook, Inc. (NASDAQ:FB) may be in trouble.

They have each stalled at resistance. If they can’t break through soon, there’s a good chance they start to trend lower.

Resistance is a large concentration of sellers trying to get the same price. At resistance levels, there is more supply than demand for shares. This is why rallies end or stall when they reach these levels.

If stocks hit resistance and can’t break through it, they tend to trend lower. This is what happened when GOOGL and FB reached their respective resistance levels in late April. There’s a chance it happens again.

For Facebook, the resistance is at the $330 level.

The $2,390 level is resistance for Google.