Per the newest TO for the Headquarters and Service Company of Marine Rifle Battalion 1037F dated 2 Feb 99.
There is no longer STA. The Scout Snipers fall into the sniper platoon of the S2 (Intel) section. The term STA is no longer on the TO/E since the GSR and RBSS where taken out of the Battalions a few years earlier.
The Company headquarters is not considered a platoon, but the company headquarters, It has a total 2 officers and 4 enlisted Marines, the company clerks no longer exist, the are temp fill billets Marines take from the company to work in the office, but go back to their platoon when they go to the field.
Infantry Battalions have 3 regimentally lettered line companies, a weapons company and the Headquarters (Headquarters and Service) Company.
The weapons company has TOWs, 81s, Javelins (phasing out Dragons) and Heavy Guns.
The East Coast infantry regiment have 3 Battalions, but West Coast can have 3 or 4 battalions, depending on if they picked up a battalion from 4th Marines, when all the Battalions where moved from Oki to the CONUS. The largest element in the Infantry regiment is the H&S Company of the Regt. Most times the Regiments have only 2 of their 3 or 3 of their 4 that actually fall under the Regt Command, since the other is deployed.