Official NetBattler

An Official NetBattler (オフィシャルネットバトラー) is a NetBattler from the Mega Man Battle Network series that has license to Jack-in and NetBattle anywhere to help the NetPolice fight against Net-crime.

Video games
Eugene Chaud is an ace Official NetBattler that appears in all games from the series. In Mega Man Battle Network 2, a secret Official NetBattler meeting is held in Netopia to discuss about Gospel. Princess Pride infiltrated the meeting to deal with its members, but she is stopped by Lan Hikari.

City NetBattler
A City NetBattler (しみんネットバトラー) is a civilian NetBattler that can represent Official NetBattlers when they are not available and can accept requests from citizens in the Official Center in Marine Harbor, helping in tasks such as delete viruses, find persons, trade Battle Chips and more. Lan, Dex, Mayl and Yai all gain a city NetBattler ZLicense early in Mega Man Battle Network 2, and Lan's rank increases later. After FreezeMan's defeat, netcrime is at high and most Official NetBattlers are busy, so city NetBattlers are requested to investigate Kotobuki Square.

In the anime
In the anime, Jackass mentions in Rockman.EXE Stream that "Official" is an old term that was used for a NetSaver, known as NetSavior (ネットセイバー) in Japan, around 20 years in the past. Lan Hikari, Chaud Blaze, and Raika are the only known NetSavers.

MegaMan NT Warrior
NetBattlers can become an Official NetBattler by receiving a license, which requires the person to be above the age of 18. However, an Official NetBattler license can be given to an underaged person in certain conditions, in which they must receive permission from the Net Police. Lan received an Official NetBattler license in the end of Volume 1's chapter 5. Chaud also is an Official NetBattler, and they are the only known Official NetBattlers to obtain a license under the age of 18 due to their remarkable skills and the ability to perform Full Synchro.

Battle Story MegaMan NT Warrior
An Official NetBattler is a professional who solves computer crimes. Official NetBattlers have a license issued by the country that allows them to battle online anywhere. Chaud, Princess Pride, Mr. Famous, Masa and Tamako are Official NetBattlers.

After WWW's fall, Lan becomes a City NetBattler (written as "Private NetBatller" [sic] in Lan's license).