What happened

Hard on the heels of October's tech stock sell-off, we appear to be experiencing a new one here in November, with the Dow down 1.9%, and the tech-heavy Nasdaq down a disheartening 3% -- mostly on little news of note.

One stock getting particularly hard-hit today is Align Technology (ALGN -1.38%), the company behind those pricey "Invisalign" clear braces that your orthodontist just told you your kids are going to need. As of 2:35 p.m. EDT, Align Technology shares are down 9.1%.

Dentist posing with smiling patient pointing to white teeth

Not everyone was this happy with Align Technology's Q3 earnings beat. Image source: Getty Images.

So what

The most disheartening thing about this sell-off, of course, is that it seems to be happening on no actual "news" whatsoever -- but that's not entirely the case. Attentive readers of The Wall Street Journal no doubt noticed that over the weekend, that august publication highlighted Align Technology as one of several high-profile "tech" names that got sold off despite delivering "upside earnings surprises" last month -- suffering nearly a 27% decline in share price in the days following earnings.

WSJ also explained why, in its view, last month's sell-off happened: Regardless of how well a stock beats earnings these days, the stock market "can smack a stock to the floor unless the positive surprise is wrapped in a rosy outlook for the future." Unfortunately, "with the corporate tax cut behind them, interest rates up and a strong dollar crimping demand for exports, many companies are throwing ice water over expectations for their profits in 2019."

Now what

That's what appears to have happened to Align Technology. At last report, Wall Street analysts were predicting that Align would enjoy about a 23% increase in sales in Q4, and only a small 2% decline in earnings to $1.17 per share. In its guidance, though, Align said it's more likely that sales will grow only 20% to 22%, and earnings will range from $1.10 per share to $1.15 per share -- thus missing estimates on both the top and bottom lines.

Why are Align shares falling again today? My guess: Because The Wall Street Journal article just reminded investors of that fact.