At least insofar as the US is concerned (and note many other regulating bodies are writing their own ADs, certifying the aircraft themselves), the FAA AD is https://rgl.faa.gov/Regulatory_and_Guidance_Library/rgad.nsf..., where the actual changes operators are required to make start on page 45.
Thanks for the link. The interesting part [with some comments]:
> As proposed in the NPRM [FAA's notice of proposed rulemaking], the corrective actions mandated by this AD [airworthiness directive] include a revision of the airplane's flight control laws (software). The new flight control laws now require inputs from both AOA [angle of attack] sensors in order to activate MCAS [Maneuvering Characteristics Augmentation System; the system causing the crashes]. They also compare the inputs from the two sensors, and if those inputs differ significantly (greater than 5.5 degrees for a specified period of time), will disable the Speed Trim System (STS), which includes MCAS, for the remainder of the flight and provide a corresponding indication of that deactivation on the flight deck. The new flight control laws now permit only one activation of MCAS per sensed high-AOA event, and limit the magnitude of any MCAS command to move the horizontal stabilizer such that the resulting position of the stabilizer will preserve the flight crew's ability to control the airplane's pitch by using only the control column. This means the pilot will have sufficient control authority without the need to make electric or manual stabilizer trim inputs. The new flight control laws also include FCC [flight control computer] integrity monitoring of each FCC's performance and cross-FCC monitoring, which detects and stops erroneous FCC-generated stabilizer trim commands (including MCAS).
> This AD further mandates changes to the airplane's AFM [airplane flight manual] to add and revise flight crew procedures to facilitate the crew's ability to recognize and respond to undesired horizontal stabilizer movement and the effects of a potential AOA sensor failure.
> This AD also mandates an AOA DISAGREE alert, which indicates certain AOA sensor failures or a significant calibration issue. The alert is implemented by revision of MDS software [MAX display system]; as a result, certain stickers (known as INOP [inoperative] markers) will be removed.
> Additionally, this AD mandates adequately separating certain airplane wiring, and conducting an AOA sensor system test and an operational readiness flight on each airplane before the airplane is reintroduced to service.
> Finally, this AD requires that operators that wish to dispatch airplanes with certain inoperative systems must first have incorporated specific provisions that are more restrictive into their existing FAA-approved MEL [minimum equipment list; defining what can be broken and you can still take-off].
