The Snow MARPAT pattern was created by Hyperstealth for the US Marine Corps in 2006 by adding a subtle digital grey to the solid white overwhites to mimic shadows in the snow. The pattern was trialed at January 2007 at the Mountain Warfare Training Center in Bridgeport, California and at Elmendorf Air Force Base in Alaska. All items are made from a thin, lightweight tear-resistant nylon fabric for maximum packability and are meant to be worn over more insulating layers (source: https://www.hyperstealth.com/USMC-Snow-Camouflage/). This pattern is still currently (as of September 2022) in use for winter training.
Parka:
Tag:
Inside:
Pass-Through Lower Pocket Slit:
Internal Zipper Pocket:
On lower inside of right side (as worn).
Hood:
Button:
Pants:
Pants are made from the same material as the parka.
Tag:
“Validation Test” NSN. 
Normal NSN.
There are two versions of the tag, one with a normal NSN and another with “USMC Validation Test 2007”. Both are identical in design.
Button and Waist Cords:
Zipper Fly:
Inside:
Pockets:
Internal zipper pocket on right side (as worn). The other side has a pass-through slit.
Ankles:
Elastic at ankles.
Wild Things Pants:
The Wild Things version is made from a slightly different fabric than the ones shown above.
Tags:
The Wild Things pants have later 2014 contract dates.
Back Pocket External Tag:
Inside:
Waist Drawstring:
Pass-Through Pocket Zippers:
Waist “pockets” are pass-through slits secured by zippers.
Ankles:
Ankles are secured by a zipper like the Patagonia PCU.
Pattern Comparison:
The Wild Things versions use a slightly different version of the pattern compared to the original (“Standard Mfg. Co.”) with slightly different shapes and lighter greys, though this tone difference may be due to the slightly different material.
Usage Photos:
Initial Test (January 2007):
Winter Training:
Jan. 24, 2011: A shooter and his spotter prepare a shot during the Mountain Scout Sniper Course at Marine Corps Mountain Warfare Training Center, Bridgeport, Calif (Photo 20110124-M-3909A-463 by LCpl Sarah Anderson, from https://en.wikipedia.org/wiki/MARPAT#/media/File:Scout_sniper_snow_MARPAT.jpg). 
Nov. 20, 2020: U.S. Marines with Marine Rotational Force-Europe 21.1, Marine Forces Europe and Africa, hike through snow during a cold weather live-fire training event in preparation for Exercise Reindeer II in Setermoen, Norway. Reindeer II is a bilateral training exercise hosted by the Norwegian military to increase support capabilities between NATO allies in extreme conditions (U.S. Marine Corps photo by Cpl. William Chockey, from https://www.marines.mil/News/News-Display/Article/2435403/us-marines-complete-norway-deployment-for-arctic-warfare-training/).
Regulatory Information:
DISCLAIMER: The following is not legal advice and is a summary of United States regulatory information found through research with open source/publicly available materials. kommandopost.com is NOT responsible for any legal, financial, or any other consequences you may incur by using this information. Please consult YOUR lawyer for YOUR specific case; I am not a lawyer and cannot help you with this, and YOU are responsible for compliance.
Snow MARPAT items have a DEMIL code of A (source: https://www.parttarget.com/8415-01-555-0414_8415015550414_OWPAR03-MEDIUM-LONG.html), which means that it is “Non-USML/non-CCLI – no DEMIL or DOD TSC required. Department of commerce may impose licensing requirements to certain destinations. (NOTE 9)” (source: https://www.parttarget.com/nsn_glossary.html/-FC7910CC-DFB5-4061-B98B-1CBE092DDB12#letter_D). Specifically, this means that EAR99 applies: “Items subject to the Export Administration Regulations (EAR) in parts 773-74 of Title 15, Code of Federal Regulations (CFR) (CCLI or EAR99) and determined by the DoD to present a low risk when released out of DoD control. No DEMIL, MUT or end use certificate is required. May require an export license from DOC” (source: https://www.dla.mil/Working-With-DLA/Federal-and-International-Cataloging/DEMIL-Coding/DEMIL-Codes/). They are also coded under “Schedule B 9803100000: military wearing apparel of all types and materials, including footwear and headwear.” for export (source: https://www.iso-group.com/NSN/8415-01-555-0389).