Regulation FD
Also called Reg FD, fair disclosure.
The SEC rule against companies sharing material nonpublic information with a select few before the public.
Adopted in 2000, Regulation FD requires that when a company discloses material nonpublic information to people such as analysts or investors likely to trade on it, it makes the information public at the same time, or promptly if the disclosure was unintentional. Source 1
An 8-K under Item 7.01 is one way to make it public. Source 1 Source 2