Shares in Staples Inc. (SPLS) hit a 13-year low on Tuesday, just one day after the Federal Trade Commission filed suit to block the company from acquiring rival office supplies retailer Office Depot (ODP).
The company opened trading on Monday morning at $12.28 per share, which gave it a market cap of around $7.9 billion. It would close down 13.2% to $10.66 per share, and was down to just $9.83 per share as of this writing at around 2pm on Tuesday afternoon.
That means Staples has shed around $1.6 billion in market cap in the past 24 hours, but that doesn’t even tell the whole story.
Shares in the Framingham, Mass.-based company closed at $19.40 per share on February 3, which was the day before it announced its deal for Office Depot.
That worked out to a market cap of around $12.5 billion. Now the company is worth just around half that, and just a hair above the original $6.3 billion purchase price for Office Max (which has since shrunk, since part of the deal included Staples stock).
Get Term Sheet, our daily newsletter on deals & deal-makers.