How does this work at companies that are very distributed geographically? The WARN act talks about "mass layoff affecting 50 or more employees at a single site of employment."

I'm genuinely asking this question - I'm not trying to be a smart ass.

I worked at a tech company (~3500 worldwide) that had an office in almost every major US city area (e.g. Bay Area, NYC, Boston, Chicago, Seattle, and a bunch of Tier 2 cities as well (Atlanta, Raleigh, Houston, etc), and remote workers (e.g. sales) as well.

They had a big layoff and in theory they could laid off 500/15% people worldwide without laying off 50 people at each site. Would that still trigger the WARN act?