Core terms
Reg SHO
Regulation SHO is the U.S. equity short-selling framework covering order marking, short-sale price tests, locates and delivery-failure close-outs. A threshold list is only one part of it.
What traders should verify
Identify whether a claim concerns Rule 201, broker borrow arrangements or a dated threshold list. In FennEdge’s Reg SHO tool, check the list date and follow the official source before recording the observation.
Do not conflate
“On Reg SHO” usually means threshold-list membership. It does not by itself establish illegal naked short selling, an SSR trigger or a squeeze deadline.